[lockeed]

Hey Guy, I just bought a 01' 740i last week and brought it back home to start diagnosing multiple issues. Today I connected my Foxwell 630 scanner on the car and went through the codes, as well as the ABS and airbag modules and their respective codes... I'm able to erase the ABS codes but they always come back, but I can't erase the airbag module codes for some reason.

Again, the car is new to me, the front right door card was removed when I got it, as well as the door airbag, which I since reconnected., and hooked the battery back up. I scanned all airbags individually and all are "active" and detected, and seat belts switch are operating normally. It's very possible that the car was neglected and both the ABS module AND the airbag module are bad and need replacement...Or it was in a minor crash and was put back toguether by an amateur who never bothered to chase the warning light situation.

I also remember seing 3 separatre code in the airbag diagnostic section, one of which was a "power supply" code linked to the airbag module. (I can check and report back precisely if need be) So I find it pretty weird that both modules would do that at the same time... Can these modules be linked by a single element, like the BST battery cable, or a blown 40/50amp fuse or something of that nature?

Let me know what you guys think and how I should start to diagnose these issues. Like checking for voltage at both modules I presume...

Thanks!

 

[M_Bimmer]

Your AMS/DSC Control Unit (A65) is powered via:

• F108 50Amp Fuse
• F33 25Amp Fuse
• F17 10Amp Fuse

Your Battery Safety Terminal (G24) is connected to your A12 module Connector X1081, via pins 36 and 38

Your Airbag Diagnotic Module (A12) is power via:
- F45 5Amp Fuse

A12 Airbag diagnostic module
Plug connector overview

Number	X-pin, colour	Description
X1081	50-pin, black	Plug connector Airbag diagnostic module

Pin assignments at plug connector X1081

Pin	Type	Description /Signal type	Connection /Measuring notes
1	A	Ignition circuit, driver's belt tensioner	Belt tensioner, driver's side
2	M	Ignition circuit, driver's belt tensioner	Belt tensioner, driver's side
3	A	Ignition circuit, passenger's belt tensioner	Belt tensioner, passenger's side
4	M	Ignition circuit, passenger's belt tensioner	Belt tensioner, passenger's side
5	E	Voltage supply terminal R	Fuse F45
6	M	Ground	Ground connector
7	A	Warning lamp	Instrument cluster
8	E	Belt signal	Passenger's seat belt buckle switch
9	E/A	Diagnostic link TXD	Connector TXD
10	A	Ignition circuit, driver's airbag	Driver's airbag gas generator
11	M	Ignition circuit, driver's airbag	Driver's airbag gas generator
12	E	Belt signal	Driver's seat belt buckle switch
13	A	Ignition circuit, passenger's airbag	Passenger's airbag gas generator 1
14	M	Ignition circuit, passenger's airbag	Passenger's airbag gas generator 1
15	E	Seat occupancy protection	Electronic seat control
16	A	Ignition circuit, driver's door side airbag left-hand drive Ignition circuit, passenger's door side airbag right-hand drive	Inflator assy for side airbag, driver's door left-hand drive Inflator assy for side airbag, passenger's door right-hand drive
17	M	Ignition circuit, driver's door side airbag left-hand drive Ignition circuit, passenger's door side airbag right-hand drive	Inflator assy for side airbag, driver's door left-hand drive Inflator assy for side airbag, passenger's door right-hand drive
18	A	Ignition circuit, passenger's door side airbag left-hand drive Ignition circuit, driver's door side airbag right-hand drive	Inflator assy for side airbag, passenger's door left-hand drive Inflator assy for side airbag, driver's door right-hand drive
19	M	Ignition circuit, passenger's door side airbag left-hand drive Ignition circuit, driver's door side airbag right-hand drive	Inflator assy for side airbag, passenger's door left-hand drive Inflator assy for side airbag, driver's door right-hand drive
20	A	Signal, side airbag sensor	Left front sensor (airbag)
21	A	Signal, side airbag sensor	Right front sensor (airbag)

 

[lockeed]

Awesome information, as usual. Thank you sir, I’ll report back.

 

[lockeed]

I digged deeper today and checked every single fuses. I found only one 30A fuse burned and it's #16 if I recall, something to do with the passenger electric seat, which wasn't working and now is back up, but doesn't move fw or backward... I'll have to look under the seat to figure it out a bit later...

But other than that, everything is normal, I lifted the carpet in front of the passenger seat to check the 50A fuse and everything is good and clean. I connected INPA and read the code for both ABS and airbag modules. ABS has 1 fault is it has to do with the precharge pump... Airbag has 4 codes, but being in german it was hard to translate, but looked to be the same codes I was able to pull with my Foxwell 630 scanner/programer... All point to a faulty ABS module and an Airbag module that needs a reset. At this point and all the codes reappear in a matter of seconds when I erase them.

If I missed something or you guys think I could try anything else before ordering the parts, I'm listening!

 

[M_Bimmer]

This might be a bit easier on you if you could get your issue assessed by ISTA+. Anyway you could have a friend near you use ISTA?

Your second option is to post the BMW code...the text isn't really needed.

Cheers.