DIY C245 Station wiring problem - Page 1
Forum section: electronics / beginners

author: Gorrillasnot
author_rank: Contributor
timestamp: January 16, 2025, 08:19:53 pm
content: I bought a cheap T12 & Jbc245 controller board, a pre assembled C245 handle, and a couple c245 tips from aliexpress, but have already ran into problems.First power up and the c245 tip got bright red no matter what the temp was set at.I contacted the seller and they said "incorrect wiring" but of course didn't elaborate or tell me the correct way to wire.Looking at the controller board with the GX12 connector facing me and the notch on top going counter clockwise I have it wired 5. + Red wire, 4. (should be ground but my handle doesnt have a black wire so I am confused) Jumper wire from it to pin 3, Pin2. is the blue wire for temp sensor and pin 1 is supposed to be a white wire for sleep detection, but is empty because my handle doesnt have sleep detection...does this sound right?thanks

author: thm_w
author_rank: Super Contributor
timestamp: January 16, 2025, 11:24:18 pm
content: So 4/3 is a green wire then?Maybe probe the handpiece itself to make sure the wire colors match up with what is shown on the diagram. But you'll have to do this with the soldering tip removed.Could also check output FET is not failed short.Link to listing?

author: floobydust
author_rank: Super Contributor
timestamp: January 17, 2025, 01:49:40 am
content: OP you need to post pics of the controller board backside.There's no wiring problem that can cause the heating element to stay on, it's a high-side P-ch mopsfet switch.Unless the thermocouple is stuck reading low. What does the temp display show?

author: Gorrillasnot
author_rank: Contributor
timestamp: January 17, 2025, 01:54:09 am
content: Yep pin 3 has the green wire, pin 4 which should be ground according to the listing had nothing attached but as best as i can tell pin 3 should be jumpered to pin 4 for the ID function to work so I ran a jumper wire between 3 and 4.https://www.aliexpress.us/item/3256806160550000.html?spm=a2g0o.order_list.order_list_main.46.79551802jsDuNQ&gatewayAdapt=glo2usaIve got more problems now..After rewiring the handle I seem to have let the smoke out on whatever the component circled in the pic is. (the red wire in the pic is the jumper between ID pin 3 and Ground pin 4..it was easier to do here then inside the handle)I ordered another identical controller from the same seller..hopefully I have better luck with it and also can identify the value of the blown part so I can try to repair and keep the first one as a backupthanks

author: thm_w
author_rank: Super Contributor
timestamp: January 17, 2025, 10:39:23 pm
content: In the ali listing their photo seems to match the color diagram shown above.You can trace out the circuit, can't remember if its PFET or NFET (PFET if it goes to the + side). But anything 40V and say 8A+ should be OK. SOIC8 package.For testing you can probably also use 12V in to limit the power draw and reduce chance of things blowing up.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: January 18, 2025, 12:11:06 am
content: Once the tip has gotten that hot, I doubt whether it will still work.And because mine warms up from zero to solder temp in a handful of seconds, you don't have much time to test.The heating element is also used as a thermocouple in these things as far as I know.Both schematics and (alternative?) firmware for these things are easy to find. Have you looked at a schematic? Traced some wires? There are probably a bunch of different chinese clones, and there may be small differences between them.Is that a mercury switch?Eeuw. My version is from KSGER it uses metal to metal contact in the holder itself to sense whether the iron is resting or active.

author: Gorrillasnot
author_rank: Contributor
timestamp: January 18, 2025, 02:28:00 pm
content: thanks for the info everyone..as a noob I really appreciate it.Every one of the various C245 controllers I looked at on aliexpress say Auto recognize T12 or C245 tips then goes on to say must match the wiring, so I am confused on how that's supposed to work. I bought a pre assembled C245 handle and figured it would be plug n play, but I am not that lucky..lolA good sugestion was to probe the handle without the tip, but I'm not sure how to do that..The tip end seems to be solidly glued together so I am not sure how I could get to the proper wires/pins to probe it.As a replacement for the blown chip I have..would a 4882 or 4614 work?thanks

author: Vovk_Z
author_rank: Super Contributor
timestamp: January 19, 2025, 09:32:25 am
content: I just googled T12 pinout and found a different one. 🤔

author: floobydust
author_rank: Super Contributor
timestamp: January 19, 2025, 11:38:38 pm
content: It's a 30V laptop mosfet, look at AO4409 etc: They won't survive a short-circuit.https://www.eevblog.com/forum/repair/brand-new-ksger-t12https://www.eevblog.com/forum/reviews/ksger-t12-solder-station-ao4409-alternatives-please!!

author: thm_w
author_rank: Super Contributor
timestamp: January 20, 2025, 09:52:13 pm
content: Quote from: Gorrillasnot on January 18, 2025, 02:28:00 pmThe "auto recognize" is recognizing the resistance between 3 and 4. So in this case with T245 its 0 ohm, then in the T12 case its some resistance they show in the ali listing. Its just the easiest way for them to do it, JBC does the same thing.QuoteStick a wire inside, the top contact should be easy to probe but the middle and bottom are difficult.

author: Gorrillasnot
author_rank: Contributor
timestamp: February 09, 2025, 04:53:59 pm
content: Update: I ordered a new controller and t245 handle from aliexpress. I was finally able to find a video on how to rewire the handle to work.It now works awesome!I also ordered some 4459A mosfets (hopefully it was the right choice) to repair my original c245 controller. After swapping the mosfet and powering on the controller the screen works as normal and I can go through all the menus and settings, but the tip will not heat up.Did I chose the wrong mosfet or is there another component on the board I should test?thanks

author: thm_w
author_rank: Super Contributor
timestamp: February 10, 2025, 10:24:41 pm
content: AO4459 looks right if the original was P-Channel, which I can't say for sure based on the detail in the photo but probably.Use a voltmeter to measure the gate and output of the FET, turn the temperature down below current temp and above current temp, etc.

author: Gorrillasnot
author_rank: Contributor
timestamp: February 24, 2025, 06:22:50 pm
content: Fixed: I bought a cheap hot air gun and hit the chip with it and the controller now works.thanks everyone