C-ZERO Fault code P1A2A

[Neo5]

Hello everyone,
I'm experiencing a breakdown on my 2012 C-Zero with a total of 110000km,
The car starts and goes into ready mode, as soon as I change gear P -> R / N or D, the light of the car with the exclamation mark appears, the car remains motionless no reaction to the pedal.
The 1st time the problem occurred the car had been stationary for 1 week outside (it rained a lot) and there was a bang at the rear when starting.

12V battery ok (less than a year old)
Car charges

fault code P1A2A

Anyone know the problem?

 

[kiev]

Welcome to the forum, sorry to hear of your trouble. We have never had this code reported that i can recall.

The P1A2A DTC refers to

• Malfunction of the EMCU IGBT system

Unfortunately that is likely a blown Integrated Gate Bipolar Transistor in the motor control unit that you heard make the loud pop--that is what they do when shorted and blow.

There are 3 of them located below the big black capacitor in the MCU, and there is a thread here with pictures of the internal works of the IGBT.

https://myimiev.com/threads/motor-control-unit-mcu-details.2844/

i think this was posted before but i'm not finding it quickly, but here is the guts of one transistor

 

[Neo5]

Hello Kiev,

Thank you for all this information, not having found much on the internet you enlighten me a lot

I'll update the thead when I disassemble the MCU, if it confirms what you say

Do you think that just by replacing the transistor it is repairable? or if it is HS you must plan to replace the MCU

 

[kiev]

i think it is fairly easy to remove and replace a damaged transistor. i'm not sure where that part could be ordered but i haven't searched.

Of course another failure might be to the big black capacitor itself. Never seen or heard of that happening, but it would make a loud bang.

Basically you would need to remove the cover and inspect, check, test, verify the components, hopefully find a culprit and replace it. All the high power stuff is in the top plenum, the control and logic board is in the bottom plenum.

 

[MickeyS70]

Hi there

Some useful info from the service manual

http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2013/54/html/M154930440003200ENG.HTM

 

[Neo5]

Hello

I found some time to disassemble the MCU.
Here are some pictures but i don't see anything special.
Except for this spot with a bubble and a black spot.


Maybe you see something wrong?

 

[kiev]

It looks blown to me, but can you get a closer picture for more resolution of just that upper section with the damage, to be sure?

 

[Neo5]

It looks blown to me, but can you get a closer picture for more resolution of just that upper section with the damage, to be sure?

The forum reduces the image I uploaded to an image host

https://gcdnb.pbrd.co/images/p3u5J5Srrio6.jpg
https://gcdnb.pbrd.co/images/sLwKHocO7M0U.jpg

 

[kiev]

Those are great pictures. The marked block appears as damage in that picture, but looks almost okay in the other one showing all three. You would need to be looking for broken or burned bond wires, or burned and blown out pads on the silicon. i looked at all three and couldn't find anything obvious except the red marked block--can't tell if the bond wires are damaged or not.