Technical Is this the answer? ECU fix !!!!

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Technical Is this the answer? ECU fix !!!!

Your photo in not clear enough for me to see but the yellow part looks to be an smd inductor or capacitor,however if the one next to it has the same part number you should be able to identify it by testing the adjacent one,as for the dry joints on the socket I would suggest you re solder every one and not just the ones that look bad because as the pin warms up due to either current drawn through the pin or heat from the engine a microscopic crack can open up that may not be visible to the naked eye when cold.It would be a big mistake to just solder up the bad looking one.
 
I agree with Michael. Definitely re-solder all pins not just the obvious one.
You other errors such as airbag failure and door open have nothing to do with this ecu. Let`s focus on trying to repair this one for the time being.
Yellow thingy looks like a smd capacitor to me. Try to order new ones from somewhere. Aliexpress is the place to look for these things - 20 or so pieces could be yours for peanut money
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After replacing the smd capacitor and resoldering the pins you should be good to go, but do not place it back to its original postion - move it to the battery tray instead, this is very important. If I find more info about this yellow smd thing I will post it here.


https://www.aliexpress.com/store/pr...343-spot-Free-shipping/734937_1509541716.html
Edit: Here it is , as promised . You get the idea what to look for. Keep us posted about your progress
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I agree with Michael. Definitely re-solder all pins not just the obvious one.
You other errors such as airbag failure and door open have nothing to do with this ecu. Let`s focus on trying to repair this one for the time being.
Yellow thingy looks like a smd capacitor to me. Try to order new ones from somewhere. Aliexpress is the place to look for these things - 20 or so pieces could be yours for peanut money
smile.gif



After replacing the smd capacitor and resoldering the pins you should be good to go, but do not place it back to its original postion - move it to the battery tray instead, this is very important. If I find more info about this yellow smd thing I will post it here.


https://www.aliexpress.com/store/pr...343-spot-Free-shipping/734937_1509541716.html
Edit: Here it is , as promised . You get the idea what to look for. Keep us posted about your progress
wink.gif
yeahthat.gif

Visconti and Michael have correctly identified the yellow component as33uF capaciter (a tantalum electrolytic to be precise.It's not unknown for these to fail on their own. It's likely to be in the power supply circuit. It's failure would like not stop operation competely but could lead to all sorts of weird problems. When replacing it make sure there are no burnt out tracks.

Robert G8RPI.
P.S. if anyone closer to me want's help with ECU soldering I'm happy to help.
 
@Michael Dranfield, @Visconti, @g8rpi - Thank You for your replies, I will try to follow your advices. Actually I already resoldered almost all the pins, but switching the burnt capacitor is still one fault to fix...

I bought a chinese fake VAG COM cable, with a CH340T chip - at the end of the day, after screwing up hours while trying out drivers and stuff, finally I was able to connect to the ECU using unregistered (not for too long, I will buy the full version, when my proper ELM327 USB cable arrives) MES.

I attached an image which shows the stored errors according to MES. It looks a bit worrying to me. I clicked the clear errors button, and now I cannot read the whole description of the single errors. After restarting the car, blipping once the throttle, shutting it down almost inmediately, and then reconnecting to MES - I experienced no errors, even though the engine was running like before. I guess I should have waited for longer or just go for a ride, to reproduce the previously stored errors.

So ...
P0201 - Cylinder 1 injector - No signal - Stored - Light ON
P0300 - Ignition failures (generic) - Signal low - Fatal - Light ON
P0301 - Cylinder 1 ignition failures - Signal low - Fatal - Light ON
P0136 - Lambda 1 Signal below catalyser - Signal low - Stored - Light ON
P0302 - Cylinder 2 ignition failures - Signal high - Stored - Light ON

Where should I go next? New ignition cables + coils (at Cylinder 1+2) + spark plugs, and also new injector (at Cylinder 1), and new Lamda sensor?

Thank you for your help in advance!
w21.
 

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So ...
P0201 - Cylinder 1 injector - No signal - Stored - Light ON
P0300 - Ignition failures (generic) - Signal low - Fatal - Light ON
P0301 - Cylinder 1 ignition failures - Signal low - Fatal - Light ON
P0136 - Lambda 1 Signal below catalyser - Signal low - Stored - Light ON
P0302 - Cylinder 2 ignition failures - Signal high - Stored - Light ON

I've got some more news:
- I checked all the spark plugs and coils. Good thing is that there wasn't any sign of oil or water or any kind of goo on the spark plugs / end of coils.
- Cylinder 1 spark plug was noticeable more black, burnt and (petrol) smelly, so this can be a proof of misfire in Cylinder 1. Others looked perfectly healthy.

After messing with the plugs and coils I went to check the D81 connector - especially the resistance between the 12V pin and the other ones. I attached an image to present the result of measuring the resistance between each pins.

So the "left" pin showed more than double resistance then the others... What should I do next/now? Maybe this causing inaccurate injection and that's why the spark plug is so burnt out in Cylinder 1? Or maybe Injector 1 is dying?

Thanks for the help in advance!
 

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I would suggest that you repair the ECU first, replace that burnt out condenser/capacitor and continue from that point. You could go on like this changing coils and plugs etc, with no effect if the ecu is still not working properly (which it is not because of the burnt capacitor).


Only after you make sure the ecu is ok it is possible to go on with the diagnosis.


Regards,


Visconti
 
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Swap coils 1 and 3 and see if the problem moves is an easy free check. Tantalum capacitors popping is often a sign of overvoltage I would check the alternator voltage.
 
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