Abstract:
A machine for replacing used transmission fluid in a vehicle with new transmission fluid includes a frame having a housing. The machine includes a pair of service hoses that extend from the machine and connect to the vehicle&#39;s transmission fluid system for placing the machine in the fluid flow. A new fluid tank and a used fluid tank are provided. A pump and a manifold are associated with each of the tanks. The pumps provide for the selective withdraw or insertion of fluid into or out of the tanks. A display on the housing presents an operator of the machine with various tasks or options the machine can perform. A processor controls activation of the pumps and other electrical components based on inputs received by the display. Scales are provided under each tank for determining the amount of fluid going into and out of the tanks during the exchange process.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of and priority to commonly owned U.S. Provisional Application Ser. No. 61/638,121, filed Apr. 25, 2012, which is hereby incorporated by reference in its entirety. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     TECHNICAL FIELD 
     The present invention relates generally to an apparatus for removing used transmission fluid from an automobile and replacing the same with new automatic transmission fluid (“ATF”). 
     BACKGROUND 
     As readily understood in the art, automobiles have a transmission fluid in the transmission to reduce the wear between mechanical parts of the transmission. The fluid must be cooled during operation of the vehicle and, accordingly, the transmission fluid sub-system includes a pump which circulates the transmission fluid through the transmission and to and from a radiator via hoses such that the radiator can cool the transmission fluid and return cooled fluid back through the transmission. During the course of operation of the vehicle, the transmission fluid can break down and/or get dirty. The makeup of the transmission system does not lend itself to simply removing a drain plug and draining out used transmission and replacing it with new transmission through a dip stick or fill tube, like with oil changes. Consequently, it is known to insert a fluid exchange machine into the transmission sub-system by disconnecting one of the hoses to or from the radiator and inserting the transmission fluid exchange machine into the system. 
     SUMMARY 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith and in which like reference numerals are employed to indicate like parts in the various views: 
         FIG. 1  is a perspective view of an embodiment of a transmission fluid exchange machine of the present invention hooked to an automobile to perform an exchange service; 
         FIG. 2  is a front perspective view of the machine of  FIG. 1 ; 
         FIG. 3  is a rear perspective view of the machine of  FIG. 1 ; 
         FIG. 4  is a right side perspective view of the machine of  FIG. 1 ; 
         FIG. 5  is a left side perspective view of the machine of  FIG. 1 ; 
         FIG. 6  is an enlarged, exploded, perspective view of the machine of  FIG. 1 , from a front, top, right vantage point, and with a frame and housing removed to reveal various components of the machine; 
         FIG. 7  is an enlarged fragmentary view of a portion of the machine of  FIG. 1  illustrating a flow tube; 
         FIG. 8  is an enlarged fragmentary view of a portion of the machine of  FIG. 1  illustrating a valve control lever; 
         FIG. 9  is an enlarged fragmentary view of a portion of the machine of  FIG. 1  illustrating an area with funnels for adding various fluids to the machine; 
         FIG. 10  is a schematic flow diagram illustrating a flow of fluid through the machine of  FIG. 1  when in a bypass mode; 
         FIG. 11  is a schematic flow diagram illustrating a flow of fluid through the machine of  FIG. 1  when in a first exchange mode; 
         FIG. 12  is a schematic flow diagram illustrating a flow of fluid through the machine of  FIG. 1  when in a second exchange mode; 
         FIG. 13  is a schematic flow diagram illustrating a flow of fluid through the machine of  FIG. 1  when in a chemical injection mode; 
         FIG. 14  is a schematic flow diagram illustrating a flow of fluid through the machine of  FIG. 1  when in an empty used fluid tank mode; 
         FIG. 15  is a schematic flow diagram illustrating a flow of fluid through the machine of  FIG. 1  when in an empty new fluid tank mode; and 
         FIGS. 16-47  are drawings illustrating sample user interfaces displayed on a display of the machine for operating the machine of  FIG. 1  to perform various tasks. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings in more detail and initially to  FIG. 1 , numeral  10  generally designates a transmission fluid exchange machine constructed in accordance with an embodiment of the present invention. The machine  10  includes a cart-like frame  12  that sits on casters  14  to enable an operator to roll the machine  10  to a vehicle  16  to be serviced. Sitting in the frame  12  are two fluid tanks  18 ,  20  of preferably comparable size. One of the tanks  18  will store the removed, used automatic transmission fluid, while the other tank  20  will store new automatic transmission fluid. Above the tanks  18 ,  20 , the frame  12  includes a housing  22  that conceals various components of the machine  10 , which will be discussed in greater detail below. On the exterior of the housing  22 , as seen in  FIG. 2 , there is a display  24 , a sight glass or tube  26 , a pressure gauge  28 , a valve control lever  30 , and a pair of funnels  32 ,  34 . On the left side  36  of the housing  22  are hooks  38  which hold two hoses  40 ,  42  that connect to the vehicles&#39; transmission system  44  to bring fluid into the machine  10  and send fluid back out of the machine  10 . 
       FIG. 3  shows a rear view of the machine  10 . In addition to electronics that drive the display  24 , the machine  10  also has a pair of pumps  46 ,  48  which will be discussed in greater detail below. The pumps  46 ,  48  and the display  24  are powered by connecting the machine  10  to the vehicle&#39;s electrical system by way of a pair of clamps  50  that connect via cables  52  to the battery  54  of the vehicle  16 . The cables  52  and clamps  50  are visible on a rear  56  of the machine  10 , where they are held by a bracket  58 . 
     This particular machine  10 , in order to keep a balance between the amount of fluid removed and the amount of fluid replaced, uses a pair of scales  60 ,  62  to determine the weights of the two tanks  18 ,  20  during the fluid exchange process. The scales  60 ,  62  are positioned underneath the tanks  18 ,  20  and are viewable below the tanks  18 ,  20  in  FIG. 3 . Also visible in  FIG. 3  is a location where free ends  64  of the two fluid hoses  40 ,  42  can connect to the machine  10  via quick couplings  66  on an underneath side of a hose bracket  68  projecting from the left side  36  of the machine  10  (see also  FIG. 5 ). While the present embodiment uses scales  60 ,  62  to determine the volumes of the two tanks  18 ,  20 , alternate methods of determining the volume can be used. For example, optical sensors (not shown) may be placed on an underneath side of the housing to look down into the tanks  18 ,  20 . Signals can be sent down and reflected off of an upper surface of the fluids to determine the fluid level. The distance the signals travel can tell where the fluid level is in each of the tanks  18 ,  20 , which can be used to calculate the volume of fluid in each of the tanks  18 ,  20 . 
       FIG. 4  discloses a view of a right side  70  of the machine  10 . A drawer handle  72  extends outwardly from a drawer  74  in the right side  70  of the housing  22 . The drawer provides storage for items related to the machine  10 , such as manuals and parts. The drawer handle  72  also permits an operator to pull the machine  10  around to various vehicles  16  when the drawer  74  is locked in a closed position by a latch  76 . Another or upper handle  78  is partially visible adjacent an upper surface  80  of the housing  22 , but is more readily visible in  FIG. 3 . 
       FIG. 5  discloses a view of the left side  36  of the machine  10 . The two hoses  40 ,  42  are a threadably coupled with the machine  10  at their proximal ends  82  using a pair of 90° elbows  84 . The quick couplings  66  at the distal ends  64  of the hoses  40 ,  42  allows an operator to quickly uncouple the hoses  40 ,  42  from the hose bracket  68  and connect them into the vehicle&#39;s sub-system. The funnels  32 ,  34  are visible above the hose connections. In this particular figure, the funnels  32 ,  34  have lids or caps  86  placed thereon. 
       FIG. 6  is an exploded view of various internal components of the machine that are generally obstructed by the housing  22  and frame  12 , which have been omitted in this figure for clarity. The internal components include both electrical components and plumbing components. The electrical components include a printed circuit board (“PCB”)  88  that is electrically coupled to a power controller  90 , a programmable logic controller (“PLC”)  92 , and a cooling fan  94 . The power controller  90  may include a transformer and/or an inverter for regulating the power to the machine  10 . The PLC  92 , as would be understood by one of ordinary skill in the art, is for controlling various components of the machine  10 . Also coupled with the PCB  88  are motors  96 ,  98  that drive the pumps  46 ,  48 , respectively. A solenoid valve  100  is also connected to the PCB  88 . The display  24  and the scales  60 ,  62  are coupled with the PLC  92 . The PCB and PLC may be collectively referred to herein as a processor as they collectively execute computer programs and containing a processing unit and a control unit. The operation of these components will be discussed in greater detail below. The electrical components also include a plurality of unnumbered wires, cables, and connectors that permit the electrical components to be in electrical communication (i.e., electrical current and/or signals may pass between them) with each other. 
     The plumbing components, in addition to those already discussed above (e.g., the funnels  32 ,  34 , the hoses  40 ,  42 , the pumps  46 ,  48 , etc.), also includes a new fluid manifold  102  and a used fluid manifold  104 . The manifolds, in the illustrated embodiment, take on the appearance of blocks having various openings or ports  105  therein that communicate with passages or pathways  107  therethrough. The manifolds  102 ,  104  will be discussed in greater detail below. The new fluid funnel  32  includes a tube  106  that extends from the bottom thereof down into the new fluid tank  20 . The chemical funnel  34  is connected to the new fluid manifold  102  by various connectors  108  and a tube  110 . Similarly, each tank includes a fluid pickup tube  112  that is coupled with its associated pump  46 ,  48  via various hoses and connectors. The plumbing components also include a plurality of unnumbered hoses, elbows, tubes, and connectors that permit the plumbing components to be in fluid communication (i.e., fluids may flow between them via various conduits) with each other. 
       FIG. 7  is an up close view of the sight tube or sight glass or flow tube  26  of the present invention. It is viewable by the operator on the upper surface  80  of the housing  22 . The sight glass  26 , in the illustrated embodiment, is preferably a block of transparent material  113 , such as glass, plastic, or acrylic, having a passage  115  therethrough. In an alternate embodiment, the sight glass  26  could simply be a clear or transparent tube. When the hoses  40 ,  42  of the machine  10  are connected with the vehicle&#39;s transmission system  44 , the machine  10  is in a bypass mode, and the vehicle  16  is turned on, the vehicle&#39;s own transmission pump should start circulating the fluid through the vehicle sub-system and through the machine  10  in either direction. If the hoses  40 ,  42  are connected to the system  44  correctly, fluid will flow through the passage  115  of the sight tube  26  in the direction indicated by the arrow in  FIG. 7  and a bullet or slider  114  contained inside the passage  115  in the sight glass  26 , which is biased to the right side thereof via a spring  116 , will move to the left and compress the spring  116  an amount depending on the amount and force of fluid flow through the sight tube  26  and the bullet  114  (i.e., the bullet  114  has a bore therethrough (not shown) to permit the passage of fluid therethrough). If the machine  10  is hooked into the system  44  in a reverse orientation, the bullet  114  will not move and the operator realizes that the hoses  40 ,  42  are hooked into the system  44  in a backwards configuration. Fluid, however, will still flow through the sight tube  26 , the bullet  114 , and the machine  10 . Instead of disconnecting the hoses  40 ,  42  and switching them around, the operator may simply change the orientation of the hoses  40 ,  42  by using the valve control lever  30  on the upper surface  80  to correct the flow. A proper direction of fluid flow through the machine  10  is important to ensure that fluid enters the manifolds  102 ,  104  in one direction so the manifolds function properly. 
       FIG. 8  shows the valve control lever  30  that the operator may turn 90° to rotate a ball valve  118  positioned beneath the housing  22  to correct the flow of the fluid through the ball valve  118  and through the machine  10  itself. The pressure gauge  28  informs the operator of the working pressure of the fluid in the vehicle  16  and the machine  10  during operation. 
       FIG. 9  is an almost top plan view of the two funnels  32 ,  34  on the upper surface  80  of the housing  22  where an operator may add new ATF or may add chemicals to the fluid, such as cleaner and/or conditioner during the process, which will be discussed below. 
     Turning now to  FIGS. 10-15 , flow diagrams are provided to illustrate the flow of fluid through the machine  10  during various operations of the machine  10 . The flow diagram illustrates the ball valve  118  that is operated by the valve control level  30  on the upper surface  80  of the housing  22 , the used fluid manifold  104 , the new fluid manifold  102 , the used fluid pump  46  associated with the used fluid manifold  104 , and the new fluid pump  48  associated with the new fluid manifold  102 . The solenoid valve  100  is coupled with the used fluid manifold  104  and electronically changes the flow of fluid through the used fluid manifold  104  to either direct the fluid out of the used fluid manifold  104  towards the used fluid pump  46  and ultimately, after passing through a strainer  120 , into the used ATF tank  18  in the exchange mode or to the vehicle  16  by exiting out a hose  122  which flows to the new fluid manifold  102  in the bypass mode. The new fluid manifold includes four floating balls  124 ,  125 ,  127 ,  129  that direct the flow of fluid through the new fluid manifold  102  based on their location, which is dependent on the direction fluid is flowing through the new fluid manifold  102 . In other words, the new fluid manifold  102  does not include electronically operated valves, like the solenoid valve  100 . Instead, the direction fluid is flowing through the new fluid manifold  102  causes the balls to move in different orientations to direct the flow of fluid there through. 
     Both of the pumps  46 ,  48  in the machine  10  are reversible. This not only allows the machine  10  to pump fluid into their associated tanks  18 ,  20 , but to withdraw fluid from their tanks  18 ,  20 , as will be discussed below. 
       FIG. 10  illustrates the flow of fluid through the machine  10  when it is in a bypass mode. In this mode, the machine  10  is not exchanging any fluid from the vehicle  16  but is simply inserted into the fluid flow in the vehicle&#39;s system  44  such that whatever the vehicle&#39;s pump pumps out of the vehicle  16  through the machine  10  is returned back into the vehicle  16 . This mode allows the operator to determine if the machine  10  is connected into the system  44  in the proper orientation. Additionally, it allows the vehicle  16  to operate normally for a period of time, such as when a cleaner has been inserted into the vehicle&#39;s system  44  and the cleaner gets circulated through the system  44  to clean the same. 
     The two service hoses  40 ,  42  are illustrated in the upper left corner of  FIG. 10 . Either of the two service hoses  40 ,  42  may be the in-flow hose where fluid flows into the machine  10 , depending on how the hoses  40 ,  42  are hooked into the system  44 . The ball valve  118  may be rotated to connect the in-flow hose  40  to the fluid conduit that leads to the sight glass  26 . The fluid flows through the sight glass  26  down into the used fluid manifold  104 , through the solenoid valve  100  and out of the used fluid manifold  104  to the new fluid manifold  102 . With all four balls  124 ,  125 ,  127 ,  129  being in the down position, the fluid flows out of the new fluid manifold  102  through the ball valve  118  and out the out-flow hose  42  back into the vehicle&#39;s transmission system  44 . The pressure is read by the pressure gauge  28  and displayed to the operator. It should be noted that for ease of illustration and conception, the service hoses  40 ,  42  are illustrated as connected directly to the ball valve  118  when, as illustrated in  FIG. 6 , they actually are connected to the used fluid manifold  104  and then to ball valve  118 . 
       FIGS. 11 and 12  illustrate the machine  10  operating in the exchange mode.  FIG. 11  illustrates the top service hose  40  as the in-flow hose, whereas  FIG. 12  illustrates the lower service hose  42  as the in-flow hose. When the ball valve  118  is properly oriented, the used fluid flows through the sight glass  26  and down into the used fluid manifold  104 . In this mode, however, the solenoid  100  diverts the flow of used fluid out the bottom (in the drawing) of the used fluid manifold  104  down through the used fluid pump  46 , through a strainer  120 , and out into the used fluid tank  18 . In the exchange mode, the used fluid pump  46  preferably assists the vehicle&#39;s transmission fluid pump in withdrawing used fluid from the transmission. However, because the vehicle  16  is running during the process and the transmission&#39;s fluid pump is operating, new fluid must be replaced at the same volume or level as it is being withdrawn so that the level of transmission fluid in the vehicle&#39;s transmission during operation is not decreased or increased, as such could damage the vehicle&#39;s transmission. Accordingly, during the exchange operation, the machine&#39;s electrical components are monitoring the amount of used fluid removed from the vehicle  10  by weighing the used fluid tank  18 . 
     The weight of the used fluid tank  18  can be used to determine the volume of fluid in the used fluid tank  18  by a simple calculation of weight to known volume. This information is fed through the machine&#39;s processor  88  and/or  92  and is used to control the activation of the new fluid pump  48  to withdraw an equal volume of new fluid from the new fluid tank  20 . This is measured also by weight and change of weight of the new fluid tank  20 . Accordingly, the new fluid motor  98  is variable speed to control the amount of new fluid being removed from the new fluid tank  20  by the new fluid pump  48  depending on the amount of used fluid deposited in the used fluid tank  18 . In one embodiment, the used fluid motor  96  is run at a constant speed during the exchange process. In another embodiment, the speed of the motor is variable dependent on the amount of the pressure of the fluid coming out of the vehicle. If the pressure is sufficiently high with only the vehicle&#39;s own fluid pump, the used fluid pump  46  may be used very little, if at all. If the fluid pressure is very low, the speed of the used fluid motor  96  may be increased to increase the fluid flow by speeding up the used fluid pump  46  and, in turn, increasing the volume of fluid it is moving. 
     As illustrated in  FIGS. 11 and 12 , the new fluid pump  48  is activated to withdraw new fluid from the new fluid tank  20 , via one of the fluid pick up tubes  112 , which flows from the tank  20  through the new fluid manifold  102 , out through the new fluid pump  48 , back into the new fluid manifold  102  and out to the vehicle  16  after passing through the ball valve  118 . In this orientation, because of the direction of flow of the fluid through the new fluid pump  48 , balls  124  and  129  are in an up position while balls  125  and  127  are in a down position. This directs the flow of fluid through the new fluid manifold  102  in the path illustrated. 
       FIG. 13  illustrates a chemical injection mode. In this mode the machine  10  is operated to introduce a chemical such as a cleaner or a conditioner to the vehicle&#39;s system  44 . The desired chemical is poured into the chemical funnel  34  on the top of the machine  10  and the new fluid pump  48  is activated to draw the chemical down from the funnel  34 , through the new fluid manifold  102 , out through the new fluid pump  48  in a direction opposite of the flow during the exchange process, back into the new fluid manifold  102  where it mixes with system  44  fluids, and then out of the new fluid manifold  102  to the vehicle  16  after passing through the ball valve  118 . In this mode, the balls in the new fluid manifold  102  are oriented as illustrated to direct the fluid through the new fluid manifold  102  in the desired path. Accordingly, when the new fluid pump  48  is run in a first direction the pump  48  withdraws fluid from the new fluid ATF tank  20 . When the pump is operated in an opposite direction, it withdraws fluid from the chemical funnel  34 . In both directions, the fluid is forced out of the new fluid manifold  102  towards the ball valve  118  and towards the vehicle  16 . 
       FIG. 14  illustrates an empty used fluid tank mode where the machine  10  may be operated so as to withdraw used fluid from the used fluid ATF tank  18  and expel it into a suitable collection container (not shown). The used fluid will not be pumped back into a vehicle  16 , but would be deposited into a storage container where it can be sent out of the shop for recycling. This is done by connecting the free or distal end  64  of one of the service hoses  40 ,  42  (as illustrated, hose  40 ) to a used fluid bulk storage tank. The used fluid pump  46  is then operated in a direction opposite of its operation during the exchange mode. Similarly,  FIG. 15  illustrates the machine  10  in a mode where the machine  10  is used to empty the new fluid ATF tank  20 . This operation is similar to its flow during the normal fluid exchange process; however, the free end  64  of the service hose  40  or  42  is placed in a receptacle to receive the new ATF fluid. This could be used to change the type of ATF in the tank prior to a service operation. 
     The display  24  may be a monitor, a video display, a graphic display or the like and is used to direct the service technician or operator through the correct use of the machine  10  during an exchange procedure or service. This is accomplished by presenting the operator with a plurality of screenshots that tell them which steps to take. We will now walk through the operation of the machine  10  as directed by the screenshots in  FIGS. 16-47 . 
     Turning first to  FIG. 16 , an illustration of an exemplary screen that initially displays on the machine&#39;s display  24  at start up (i.e., the Home Screen) is provided. The screen gives the user the options of the programs the machine  10  can run and instructions by way of icons or buttons  126 ,  128 ,  130 ,  132 . The display  24  may be a touch screen monitor. Upon the user touching Change Transmission Fluid button  126 , the display changes to the illustration in  FIG. 17 . 
       FIG. 17  illustrates a “correct flow” selection screen that informs the operator to start the vehicle  16  and then press a “Yes” button  134 . The user then looks at the fluid flow tube  26  to see if fluid is flowing through the machine  10  correctly. If it is, they do nothing to the ball valve  118 . If it is not, they rotate it 90° via the valve control lever  30 . With fluid flowing correctly through the machine  10 , the operator presses a second “Yes” button  136  and a “Next” button (not show) will appear on the bottom of the screen. When the operator hits the “Next” button, the display changes to the illustration in  FIG. 18 . 
       FIG. 18  illustrates a selection screen that pertains to the amount or level of transmission fluid in the vehicle  16 . The operator pulls the vehicle&#39;s dipstick on the transmission and manually checks the fluid level in the transmission. If it is low and more fluid is needed to be added to get it to full, the operator presses a “Higher” button  138  until the desired amount to add shows in display window  140  (e.g., since the meter here is 0.1 quarts, if the transmission is a half quart low prior to service, the operator would tap the “Higher” button  138  five times to add a half quart). If it&#39;s full and it&#39;s right where it&#39;s supposed to be on the dipstick, then the user presses the “Full” button  142 . If the dipstick reading reveals that the transmission is overfull and fluid needs to be removed, the “Lower” button  144  is pressed an appropriate number of times to get to the proper amount to be withdrawn. The machine  10  will store this information and correct accordingly during the exchange mode. 
       FIG. 19  illustrates a selection screen that permits the user to tell the machine how many quarts to exchange, e.g., 16 quarts. The user may press the up “1 qt” button  146  or down “1 qt” button  148  to raise or lower the amount displayed in window  150 . The user could also use any of the pre-selected amount buttons  152  near the bottom of the screen. Upon selection of an amount of fluid to exchange, a “Next” button (not shown) appears and, when pressed, the display changes to the illustration in  FIG. 20 . 
       FIG. 20  illustrates a screen that queries the user to determine if any chemicals are going to be added during the process. For example, a transmission system cleaner, such as Quick Clean™ by BG Products, may be added. If adding, the operator presses a “Yes” selection button  154 . If not, the operator presses “No” selection button  154 . A transmission fluid conditioner, such as ATC Plus™ by BG Products, may also be added or not by selecting the appropriate selection button  154 . Once both selections are made, a “Next” button (not shown) appears and, when pressed, the display changes to the illustration in  FIG. 21 , if the user indicated a cleaner is going to be added, or  FIG. 23 , if no cleaner is being added. This is because the cleaner does not stay in the vehicle transmission system  44  during normal operation of the vehicle. Instead, a cleaner is simply run through the system  44  in the bypass mode for a predetermined amount of time prior to being removed via the exchange process. 
     Accordingly,  FIG. 21  illustrates a screen that queries the operator to determine how long the operator wants the cleaner to run through the system  44  before starting the exchange process. The operator selects the duration by pressing the appropriate buttons  154 , similar to  FIG. 19 , and presses the “Next” button when the desired duration is displayed in the window  150 . 
       FIG. 22  illustrates a screen that prompts the operator to pour the Quick Clean™ cleaner into the “Add Chemical” funnel  34 . After doing so, the operator presses the “Yes” selection button  154  and then the “Next” button. At this point, the machine  10  is still in the bypass mode, so the used ATF is circulating through the vehicle  16  and the machine  10 .  FIG. 23  illustrates a screen that displays the entire process for review. In the illustrated example, the screen indicates that a 16 quarts exchange will occur after injecting the cleaner and waiting for 10 minutes to allow the cleaner to be circulated through the system and that a conditioner will be added after the exchange. If all of the information is correct, the user presses the “Start Service” selection button  154 . If something is not correct, the user presses the “Back” button  156  to go back as many screens as necessary and make the desired changes. 
     After pressing the “Start Service” selection button  154 , a screen similar to that illustrated in  FIG. 24  is displayed, which indicates that the machine  10  is adjusting the fluid level in the vehicle&#39;s transmission before starting the exchange process to ensure a proper service occurs. This action takes into account the amount the user previously requested the fluid level to be changed to bring it to full and the amount of cleaner to be used. The machine  10  then switches to the chemical injection mode and displays a screen similar to that illustrated in  FIG. 25 . As discussed above, in the chemical injection mode the new fluid pump  48  is operated to draw the cleaner out of the funnel  34 , down into the pump  48  and then out into the vehicle  16 . The process screen of  FIG. 25  conveys the amount of time remaining for this step. While the pump  48  is programed to run for a predetermined amount of time to complete the chemical injection mode step, if the operator sees that all of the chemical is gone from the funnel  34 , the operator my press the “Funnel Is Empty” button  158  to cause the pump  48  to stop and the completion of the chemical injection mode step. 
     Upon completion of the addition of the cleaner step, the machine  10  displays a process screen similar to  FIG. 26  that counts down the duration that the cleaner is circulated through the system in the bypass mode. The operator may manually increase or decrease the duration at this point by using the selection buttons  154  along the bottom of the screen. 
     Upon completion of the cleaning cycle step, the machine  10  displays a process screen similar to  FIG. 27  and the ATF exchange service step begins. As used ATF is removed, a USED ATF countdown counter  160  is displayed that illustrates the quarts remaining to be exchanged. Similarly, as new fluid is added, a NEW ATF countdown counter displays the amount of new fluid left to be introduced into the system  44 . The ATF Exchanging screen also includes a “Stop” button  164 , that allows the operator to stop the exchange step should it be necessary, an “Add 1 Qt.” button  166 , and a “Minus 1 Qt.” button  168 , to allow the operator to increase or decrease the amount of fluid to be exchanged. 
     Once the exchange process is completed, the machine  10  switches back to the bypass mode and the machine  10  displays a process screen similar to  FIG. 28 . The user is prompted to pour the conditioner into the Add Chemical funnel  34 . After doing so, they press the “Yes” selection button  154  and then a “Next” button appears that, when pressed, causes the display  24  to change to a process screen similar to  FIG. 29 .  FIG. 29  illustrates an adding conditioner step. The display  24  informs the operator that the chemical is being drawn out of the funnel  34  by the pump  48  and inserted into the vehicle&#39;s system  44  and how much time is remaining for this step. If the funnel  34  is empty before the time allotted for the pump  34  to withdraw the fluid from the funnel  34 , the operator may conclude the step by pressing the “Funnel Is Empty” button  158 . The machine  10  accommodates for the volume of the conditioner being added by removing an equal amount of ATF from the vehicle&#39;s system  44 . 
     After the conditioner is inserted, the chemical injection mode stops and the bypass mode resumes. The display then shows a process screen similar to  FIG. 30  that prompts the operator to manually check the vehicle&#39;s transmission fluid level again. If the dipstick indicates a high or low fluid level, the operator informs the machine  10  how much to take out or add by way of the selection buttons  154  and then presses the “Next” button  170 . The machine  10  then either removes or adds the correct amount of ATF or does nothing if at the proper level. 
       FIG. 31  illustrates an overview screen that informs the operator of the processes that were performed. In this case Quick Clean™ cleaner and ATC Plus™ conditioner were added and 17.3 quarts of new fluid were used. The operator presses the “Next” button  170  and a second Service Complete screen,  FIG. 32 , informs the operator the service is completed, that they need to shut the vehicle  16  off, remove the hoses  40 ,  42 , check for leaks, and disconnect the power cord  52  from the vehicle  16 . Pressing the “Next” button  170  returns the display  24  to the Home Screen, illustrated in  FIG. 16 . 
     On the Home Screen,  FIG. 16 , the user may select the “Instructions” button  132 . Selecting this button  132  causes the display  24  to display a first Instructions screen, illustrated in  FIG. 33 . The Instruction screens, illustrated in  FIGS. 33-37  walk users/operators through a set of basic instructions on what the buttons do and how to operate the machine  10 . 
     On the Home Screen,  FIG. 16 , pressing the “Empty New Tank” button  128  causes the display  24  to display an Empty New ATF screen, illustrated in  FIG. 38 . The screen displays a number of prompts that the user replies affirmatively to after completing any necessary tasks by pressing each of the “Yes” selection buttons  154 . After all questions are answered in the affirmative, a “Start” button  172  appears. When pressed, the display  24  illustrates an Emptying New ATF screen, illustrated in  FIG. 39 , and the machine  10  begins emptying the New ATF tank  20  by activating the pump  48 , in the manner discussed above. The emptying function will shut off when manually terminated by the user pressing the “Stop” button  164  or at a certain level. To keep the lines full, the machine preferably does not empty all the fluid out of either tank  18 ,  20 , but leaves a small amount in the bottom of the tank  18 ,  20 . That keeps the weight scales  60 ,  62  leveled out and it causes the machine  10  to never run dry. The hoses  40 ,  42  are preferably kept full all the time as well so they are ready to go and the user doesn&#39;t have to waste about ¾ths of a quart of ATF each time the machine  10  is used. Pressing the “Empty Used Tank” button  130  displays screens illustrated in  FIGS. 40-41  and the machine  10  to remove the used ATF from the used fluid tank  18  as discussed above and in a process similar to that described in relation to  FIGS. 38 and 39 . 
     Returning to the Home Screen, illustrated in  FIG. 16 , a service the machine  10  option is available. An invisible button  174  is located on the Home Screen in the bottom left-hand corner. Pressing there brings up a Password Keypad  176 , as shown in  FIG. 42 . After entering the password, the main service screen, illustrated in  FIG. 43 , appears. The service screen is mainly for distributor salesmen or a person that works on the machine  10 . This provides for fixing the machine  10  if something&#39;s gone wrong and is not something service technicians need to have access to. Options on the service home screen are Calibrate Tank Sensors  178 , Service Counters  180 , and Diagnostics  182 . 
     Pressing the Calibrate Tank Sensors button  178  displays a process screen, illustrated in  FIG. 44 , that allows the user to recalibrate the weight scales  60 ,  62  for the new tank  20  and/or the used tank  18 , if needed. The display  24  shows the amount the machine  10  believes is present in each tank  18 ,  20 . The user visually inspects the tanks  18 ,  20  and determines if the actual volume as measured by the scale markings  184  on the sides of the tanks  18 ,  20  match the digitally displayed amount. If the amounts do not correspond, the user can recalibrate the amounts. Pressing the Calibrate New Tank button  186  results in the display of a calibrate tank sensor screen, illustrated in  FIG. 45 . 
     Here, after cleaning the new fluid scale  60 , a user puts a weight of a known amount on the new fluid scale  60 . That amount is displayed as a number (e.g., 45.58 lbs.). If that amount is accurate, the user presses the “Yes” selection button  154 . If it is not, the user presses the number (e.g., 45.58) and is allowed to move the value up or down to the correct amount, then presses the lower “Yes” selection button  154 , at which time the scale  60  is recalibrated. Pressing the “Next” button  170  returns the user to the service home screen illustrated in  FIG. 43 . 
     Pressing Service Counters button  180  displays a service counters screen, illustrated in  FIG. 46 . That screen informs the user how many total services have been performed by the machine  10  and how may since the counter was last reset by pressing the “Reset Counter” button  188 . 
     Pressing the Diagnostic button  182  on the service home screen ( FIG. 43 ) displays a diagnostics screen, illustrated in  FIG. 47 . Here the user can manually run either pump  46 ,  48  in either direction to assure they are working properly by pressing the desired selection button  154 . 
     The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those of ordinary skill in the art to which the present invention pertains without departing from its scope. Substitutions may be made and equivalents employed herein without departing from the scope of the invention as recited in the claims. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated and within the scope of the claims.