Help, power supply for diagnose ECU - Page 1
Forum section: electronics / beginners

author: jping
author_rank: Newbie
timestamp: May 31, 2012, 01:37:41 am
content: Hi, I need help for choosing a power source for diagnose and programming vehicles. The BMW is recommended Deutronic DBL800 but is very expensive.I found another the Maas SPS 50, PIHERNZ PC-55sw, Hoxin TD-14SS50, all is the same 13.8v 50A.Can work this to power supply stabilized with 13.8v car battery?Someone knows another better for connect to car batery?Thanks

author: CampKohler
author_rank: Contributor
timestamp: May 31, 2012, 01:59:05 am
content: The recommended item is a fancy electronic battery charger. Why wouldn't you just use the car's battery to do your work? Why would you need 50 amps of current? If the problem is that the car's battery is dead to start with, there are hundreds of ordinary battery chargers and electronic chargers like this B&D for US$88:http://jumpstartersbatteryz.blogspot.com/2011/03/vector-vec1093-smart-battery-charger.html

author: david77
author_rank: Frequent Contributor
timestamp: May 31, 2012, 10:19:36 pm
content: A 13,8V 50A power supply shouldn't be at all hard to find. These thing are quite common for CB radios.A simple google search came up with loads of them, all around 200-250 EUR.

author: jping
author_rank: Newbie
timestamp: May 31, 2012, 10:26:10 pm
content: The Deutronic is a power supply and charger. The battery isn't dead but the diagnose need activate any car module in the proces with engine or alternator off, require an external stabilized power supply for replace the alternator. The battery charger aren't stabilized and haven't current amperes need for the process.The diagnosis software detect the power low at 12,6v and don't allow follow the processThis Shumacher is used in USA, but the ship an taxes is very expensive for Europehttp://www.amazon.com/Schumacher-INC-700A-Automatic-Charger/dp/B002Z2Z7ZY/ref=sr_1_3?s=automotive&ie=UTF8&qid=1338499754&sr=1-3Any idea?

author: Baliszoft
author_rank: Frequent Contributor
timestamp: May 31, 2012, 10:28:59 pm
content: Ecus do not consume that much power. If the ecu is in the car, and you have to power the whole car that is another question (which i would not recommend at all btw). I am using a 20A power supply for the same purpose, and it is far enough.Edit: if you are doing diagnostics on the car (as you write in the previous post ), just hook up a plain battery charger. The voltage will unlikely to go below the threshold until you crank.

author: jping
author_rank: Newbie
timestamp: May 31, 2012, 10:46:15 pm
content: The difference between an radio amplifier, lamp, etc, and a car battery is that the car battery have power current, the radio amplifier not.Is the same if the power supply have reverse protection current?Greetings

author: jping
author_rank: Newbie
timestamp: June 01, 2012, 12:14:39 am
content: Quote from: Baliszoft on May 31, 2012, 10:28:59 pmIn the Participant's Manual. Power Supply/Energy Management explainhttp://share.qclt.com/bmw%E8%B5%84%E6%96%99/Bus%20&%20Power/POWER%20_en.pdfBattery trickle charging Electrical loads/consumer also require the battery's power supply when the vehicle is not being driven. It is therefore essential to pay attention to the battery state of charge.It is therefore necessary to trickle-charge the batteries of all vehicles which have not be moved for some time, of stationary and stored vehicles and of showroom vehicles.Here the trickle charger provided by BMW must be connected to the cigarette lighter orwith an optional adapter cable to the jumpstart terminal point.The charger is not suitable for floating operation of vehicle electrical system, e.g. during diagnosis. The trickle charger is specially designed to ensure an optimum battery state of charge in showrooms.

author: vk6zgo
author_rank: Super Contributor
timestamp: June 01, 2012, 12:43:27 am
content: Quote from: david77 on May 31, 2012, 10:19:36 pmCB radios require 13.8V at 5 A,not 50A!

author: Baliszoft
author_rank: Frequent Contributor
timestamp: June 01, 2012, 06:17:50 am
content: Quote from: jping on June 01, 2012, 12:14:39 amWell, right. You have actually answered your question. If the battery is totally flat, charge it before use. Using a flat battery may trigger some faults for sure. If the battery is flat you really need a powerful supply, no doubt. But do yourself a favour and do not do diagnostics on a car with a flat or dead battery. If you hook up a simple charger to a normal condition battery it will help to raise the voltage above the "threshold" needed for some diagnostics (of course i dont mean $20 chinese chargers), a more powerful one will even supply enough current to bleed abs brakes or operate parking brakes, etc... Though in my opinion (and based on the experience in the shops i used to work for), a good battery charger may be used. Let the cars battery do the main work, you just should help it to keep the voltage above a certain level (just as the alternator when revving). Just think twice, you hook up a 50A power supply, everything will be fine, but if the car leaves your shop (and its battery is bad), the faults may come back. Also what do you think, how may current can a cigarette lighter slot handle? Max 10A depending on the fuse, but i doubt the socket could handle any more without heating up.Just some thoughts before you go and buy a 50-70A supply. :-)

author: Baliszoft
author_rank: Frequent Contributor
timestamp: June 01, 2012, 06:27:42 am
content: Just another thougt: if you hook up a 70A power supply to a good but flat battery it will immediately begin to charge it. Of course not with 70A, but not with a the recommended way/rate for sure. Anyhow at the end you will be still there to charge the battery first, and you will need a good battery charger :-).

author: mc
author_rank: Regular Contributor
timestamp: June 03, 2012, 07:55:53 pm
content: What the original poster is looking for, is what is usually referred to as a Battery Support Unit. Depending on manufacturer, they have recommended voltages, but most are within the 13.5 to 13.8V range. High enough to ensure modules get a healthy voltage, but low enough that it doesn't start interfering with charging circuits. As for the high amp rating, a modern diesel will eaily draw more than 60A each time you turn the ignition on (set of glow plugs at 15A each, voltage multiplier in main ECU powering up, primer pump, plus lots of other modules powering up).It's principle aim is to ensure the battery doesn't go flat during diagnostics or programming. During diagnostics, you can have the ignition on without the engine running for extended periods of time, and during programming vehicles are often forced into Limp Home/Emergency mode when the diagnsotice interface takes over control of the CAN-bus and raises the voltage, and all modules turn on essential items to ensure the vehicle can still be driven. This usually includes such things as turning on enough lights so the vehicle can still be driven in darkness, electric cooling fans since the controlling module relies on the CAN-bus to know how hot the engine is, and many other things. Now given module updating can take upwards of 5 minutes, you need an external power supply to ensure the vehicle voltage doesn't drop below critical voltage before programming finishes.Yes, you might be able to use a standard battery charger, however you risk it swinging from undervoltage to overvoltage.And you'd have to be wary of using a standard regulated supply, as it needs to be capable of handling it's output from going overvoltage, otherwise it's likely to go bang when you start the vehicle and the alternator kicks in.

author: jping
author_rank: Newbie
timestamp: June 06, 2012, 09:38:20 pm
content: Ok mowicu, that's the problem so wonder if a power supply as the Maas SPS 50 work for the diagnosis

author: Baliszoft
author_rank: Frequent Contributor
timestamp: June 08, 2012, 10:16:11 pm
content: If you do not take the advice of other fellow members, then why dont you go and buy the BMW recommended equipment?!

author: jping
author_rank: Newbie
timestamp: June 09, 2012, 06:42:07 pm
content: BMW recommended equipment?...Example:You can search in Google: BMW car battery chargerYou only find for carhttp://www.realoem.com/bmw/showparts.do?model=GB43&mospid=47359&btnr=80_0495&hg=80&fg=05&hl=1Original ref. 82110406881 or 82110026663, but just is a Battery Tender 120v-1.25A with paint black and more $...The european cars no need charge the battey?…Not only for USANow you can search: Ladegerät Auto Charger BMWYou only find for car the Deutronic orhttp://www.ebay.de/itm/Original-BMW-Batterieladegerat-Ladegerat-E36-E46-E39-/200724770813?pt=DE_Autoteile&hash=item2ebc20effdbut just is a CTEK mxs 3.6 220v-3.6A and more €…Wow, the cars in USA only need 1,25A but in Europe need 3.6A… Miracle?But the problem does not end here.In the Participant's Manual. Power Supply/Energy Management says:“The charger is not suitable for floating operation of vehicle electrical system, e.g. during diagnosis. The trickle charger is specially designed to ensure an optimum battery state of charge in showrooms.”But in the Participant's Manual BMW Diagnosis, Programming and Information Systemshttp://bmtechnic.co.uk/tutorials/GT1-Manual.pdfIn the page 10 says:“The vehicle must always be supplied with external voltage during diagnosis (connect charger).”You understand these official BMW? What you choose? What charger?

author: G7PSK
author_rank: Super Contributor
timestamp: June 09, 2012, 09:53:36 pm
content: MJLorton has a video on such things, the charger will automatically take over the load as things are switched on without discharging the battery the idea is that the customer does not get their car returned with a flat battery, why an ordinary battery charger cannot be used I don't know another toy to sell to the grease monkey?http://youtu.be/S9w6MAPAAoA

author: mc
author_rank: Regular Contributor
timestamp: June 09, 2012, 10:53:05 pm
content: Quote from: G7PSK on June 09, 2012, 09:53:36 pmStandard/convetional battery chargers are unregulated, so any change in load is reflected in the battery voltage.Newer 'regulated' or dual stage battery chargers don't have the current to handle large loads, so suffer just as much.Battery support units are designed to maintain a constant voltage, and are capable of very high currents to acheive that, with the usual minimum rated current being 50A, however they also come with a hefty price tag.For general diagnostic work, a standard battery charger is good enough, as battery voltage isn't too critical.As I highlighted in my previous post, voltage spikes or voltage falling outwith limits can cause issues, especially during major programming, and with modern ECUs costing substantial amounts, all it takes is for programming to fail once and the BSU cost pretty soon becomes insignificant.

author: Baliszoft
author_rank: Frequent Contributor
timestamp: June 10, 2012, 09:16:29 am
content: 1. I have never seen anyone reprogramming (reflashing) an ECU with high loads being turned on.2. The thread starter seems to be concerned about why bmw (or any other manufacturer) requests an overpriced item to be used during diagnostics. To be the honest their official diagnostics equipments are a lot more expensive than a power supply, so i dont really see the point. If he has got the funds to use expensive diag systems, a psu should not cause a problem. IF he is using a cheaper aftermarket alternative, the psu would be the last thing i would worry about. :-)3. If anyone wants to set up a high end garage, that costs some serious money. If the budget is tight, reasonable replacements may be bought. In this case, a good quality, higher power battery charger should do the trick. If he is still worried about using just a charger, he is better getting what bmw recommends, so he wont have nightmares :-)

author: NiHaoMike
author_rank: Super Contributor
timestamp: June 10, 2012, 08:43:10 pm
content: Just use a battery charger. Automotive electronics are designed to be tolerant of bad power so it's unlikely that you'll get any problems even if you use a low quality charger. If the battery is good, it will buffer the power anyways.

author: jping
author_rank: Newbie
timestamp: June 14, 2012, 09:04:53 pm
content: I decided to buy thishttp://www.thiecom.de/thieking-ps50-sw-3-50a-netzgeraet.htmlThanks

author: Leuven
author_rank: Regular Contributor
timestamp: June 21, 2012, 01:26:42 am
content: This is something I've put together specifically for car programming/diagnostic. I sourced the 2 power supplies from ebay at £25 each, they put out 13.8V/22A each with a total of 44Acontinuous, not max. Never heard of Kyosan before but it feels like industrial quality.I think BMW recommends something like 70A to be on the safe side and I was curious to see exactly how much of a load do I have, hence the ammeter. I've used it quite a few times, from programming to diagnostic and the most I've seen on the ammeter was around 20A (ignition-on alone is 10A), although with the battery disconnected. Otherwise it can shoot up to 35-40A load, depending on how drained the battery is. Bear in mind you need at least 13V for programming, and the voltage will drop with a higher load. 13.8V for a power supply is ok though. If you disconnect the battery remember not to crank up the engine or you will fry your gear.It's not recommended to use a standard battery charger, they can occasionally 'burp' and mess up with your electronic modules. At least that's the explanation I've been given.