[nashville_bill]

My son's 2006 330i has both the air bag light and the seat belt light on the dash, and ISTA+ tells me that the problem is with module A12 and that there is an internal short to ground on pin 5.

Can anyone tell me if the replacement A12 module, that I removed from another 2006 325, will have to be programmed before it will work in his car?

If so, what is the easiest way to program it?

Thanks for your help!

nashville_bill

[gbalthrop]

Originally Posted by nashville_bill

My son's 2006 330i has both the air bag light and the seat belt light on the dash, and ISTA+ tells me that the problem is with module A12 and that there is an internal short to ground on pin 5.
Can anyone tell me if the replacement A12 module, that I removed from another 2006 325, will have to be programmed before it will work in his car?...

Perhaps you are WAAAY ahead of me on your issue, but from the way your post is worded, I have some doubts.

The A12 MRS Module has TWO (2) connectors, each with a pin #5 which is a ground for one of the MRS System components. X10179/Pin#5 is Ground (-) for Driver Air Bag via A72 Steering Column Switch Cluster, and X18069/Pin#5 is Ground (-) for the BST, G19a (Battery Safety Terminal). Here are TIS circuit & pinout showing those functions:
https://www.newtis.info/tisv2/a/en/e...system/ewDdYyW
https://www.newtis.info/tisv2/a/en/e...system/ZFVB0y1

I would be interested to know WHAT fault codes are/were saved in MRS Memory, and what EXACTLY ISTA is telling you, that you believe indicates "there is an internal short to ground on pin 5". INPA can show precise resistance in each circuit for an airbag or seatbelt tensioner (but NOT BST circuit AFAIK), and I would assume ISTA can do the same.

I don't know the answer to your question about coding (as opposed to "programming"), but INPA will tell you if each of the eight (8) Ignition Circuits is coded, so you might check to see what ISTA shows you BEFORE disconnecting or removing anything.

Please let us know what you find,
George

[nashville_bill]

Thanks for your reply.

From ISTA+

The following is stored in fault memory:

93EB Internal control unit fault
Permanent fault

Replace the following control unit:
A12 Control Module, multiple restraint system

Encode/program new control unit

__________________________________________

Notice!

The fault applies only at terminal 15.

DIAGCODE: D6577_MRS00000_90_003

[Brokea$$325i]

Fixed my 93eb fault that started after floorboard flooded. Found a small 10 pin connecter under sound matting, directly under hood release latch. Badly corroded, cleaned with alcohol and nylon brush, cleared codes, no more airbag light!