General Module 3 : 1998 740 iL - BMW Forum

stilllearning6 · 06-08-2011, 11:35 AM

I believe that my 1998 740 iL General Module 3 might be fried and /or might be causing a battery drain.

Symptoms include lacking: rear P/W, central lock, soft close/ open trunk,interior lights, glove light ,trunk 2 lights.

I am considering trying to pull the GM3 from behind the glovebox.
I read that there are 3 cables to disconnect .

If I pull the GM3 , will the car still drive ?

Jack Dabsy · 06-08-2011, 01:51 PM

You really should stay with your original post on this subject, buddy...
Multiple posting on the same subject will just confuse people that are trying to help you sort your problems.
DAZ

brettski · 06-09-2011, 06:01 AM

I don't know for sure if it will still drive, but I read that the power steering also has an input from the GMIII in the form of a solenoide. I think that you are right that there are 3 connectors on it

stilllearning6 · 06-11-2011, 07:11 AM

My experience with 1998 740 iL was that the GM3 could be removed w/o removing glovebox.
I learned that my GM3 was held in place on each left and right side by a hidden hook/ tab/ release clip .

I could not see this holding mechanism untilI disconnected the wiring cable closest to the center of the vehicle.
This is the white plastic far end , not the wider black plastic connector end.
Mine required to pry the white "hook/tab/release clip " outward away from the GM3 .
Then , I could wiggle the GM3 out .
Perhaps others will benefit from this tidbit.
The glovebox was merely opened wide and pulled upward.

Jack Dabsy · 06-11-2011, 07:53 AM

Good post matey... Was the GM3 your problem?
DAZ

stilllearning6 · 06-12-2011, 08:07 AM

Hope to isolate the issue by Monday PM .

Thanks to all for input and guidance .

I am not used to working on BMW 's , my wrenching experience is on 1988 Jeep Wrangler with feedback carburetor and 30 miles of vacuum tubing and more emission equipment than I could ever imagine.

Jack Dabsy · 06-12-2011, 08:48 AM

Yeah, Carb's and Injection systems are two different worlds mate !!!
I feel for you, honest !

stilllearning6 · 06-14-2011, 05:38 PM

Installed Autozone 49 - DL battery after a 48 hour trickle charge on the new battery .

Replaced original " fried " GM3 and all lost functions came back to life.

I can not explain the reason .
Previous battery ( 7 and half year old AutoZone 49 -DL ) was fully trickle charged and measured FULL . Swapped battery on advice of dealer techs.

Perhaps others may benefit from my experience .