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Steve
Steve, BMW Expert
Category: BMW
Satisfied Customers: 24176
Experience:  BMW Expert
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I have a 2008 BMW mini Cooper S, and witnessed some smoke coming

Resolved Question:

I have a 2008 BMW mini Cooper S, and witnessed some smoke coming from below the dash before the car went electronically mental (headlights on/off, Windows going up/down, then completely dead & wont turn over.
I have the dash out and found a PCB unit in between the steering wheel and the windscreen which is connected to the ignition (key slot) which smelt burnt and had brown marks on inspection.
I guessed this was the E.W.S unit? Part no Siemens VDO NO. EWK4 9513XBR
Is it possible to just replace this unit ? or do you have to replace the other two ECU's (footwell & engine bay) too?
This car is actually a track car, would it be possible to just bypass it for a push button start?
thanks
Adam
Submitted: 3 years ago.
Category: BMW
Expert:  Steve replied 3 years ago.

please post an image of the unit or its full BMW part number if available.

Customer: replied 3 years ago.

61.35-9147221-01 - I have since phoned BMW direct and they say it is a CAS unit.. Which if burnt out means a replacement unit and re-program

Or purchase a second hand ECU, EWS, & CAS unit with ignition and key, they get it programmed.

My concern is that the burnt out CAS is the result not the cause and it will happen again, and its a costly test to replace and try again. I cant see any obvious shorts on the loom, and the only thing that has changed electronically is a remap from a local firm taking the output upto 228hp

Expert:  Steve replied 3 years ago.

that is indeed a CAS, and the fix is indeed replacement and reprogram.

if there are no wiring shorts there is nothing common to point to as a possible outside cause. CAS units are known to fail from time to time.

Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you. Best wishes with your vehicle.

Customer: replied 3 years ago.

sorry one further thing, before I rate you

In your opinion would it be possible to blow the unit from changing the mapping alone?

The mechanic at BMW thought it might be possible to cause the alternator to over produce feeding back into the unit and cooking it?

Expert:  Steve replied 3 years ago.

Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you.

a mapping should not cause the alternator to over produce.

if the alternator was over producing I would expect a) this could be easily tested for and b) that other units, not just the CAS, would have issues.

this is very unlikely in my opinion

Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you.

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