Body Control Module question re: 2001 L100
 

RE: 2001 Saturn L100 2.2L L4 DOHC Gas MFI F 61 - about 137048 Miles

We are the original owners and I really hate to junk the car, but can not afford to waste a lot money on a lost cause. The car has manual windows, no cruise, no remote start etc. It's a very basic model with automatic transmission and A/C .

Recently the car shut down while driving on the interstate. AAA towed the L100 to my local repair shop that has been taking care of the Saturn for over 10 years? It shut down because it was out of gas - although both fuel & temp show proper values with the scanner the gauges are incorrect. I am not sure but think he mentioned there were no fault codes. At the time it shut down the fuel gauge read 1/2 tank but the scanner showed 5%, after adding fuel the car appears to be working OK with the exception of the temp/fuel gauges. Owner/mechanic said he thought the gauge problem was related to the Body Control Module and recommended going to a dealer for proper replacement & programming if I want it fixed. I have read on line dirty battery terminals can cause BCM problems so I will clean them today to see if that helps.

Not having accurate fuel/temp is an inconvenience, but I can deal without fuel/temp gauges. My real concern is the problem will continue to worsen to the point the car will not run at all. As long as the scanner gives accurate readings I may even be able to use an android app for fuel/temp levels.


My big question: Is it likely the BCM will continue to get worse until the car no longer runs?

thanks in advance

I don't know if the gauges are run by the BCM or not. But, the easiest way to check that BCM is to locate it, unplug the connector and plug it back in several times and see what happens. The plugging and unplugging will help "sweep" the contacts clean on the plug. On the S series cars, the BCM is located under the passenger side kick panel. Sometimes, cowl drains get clogged up under the wipers and water runs down inside the fender and corrodes the connection. Like I said, I don't know where the BCM is located on the L-series cars, but I'd check there to start with. Maybe Andy will pop on soon. HE knows the L series cars like nobody else here!

Thanks Rubehayseed, I'll check that as well.

Thanks,

ON Edit: I am having trouble getting the glove box out, unable to drop the door far enough to get a screw driver on the screws .

IF this will pull up for you, maybe it'll help. Otherwise, just Google it. That's what I did in order to find this. You'll just have to click the X in the middle about the frigging BMW to get that out of the way.

https://www.google.com/search?q=saturn+L+series+glove+box+removal&tbm=isc h&source=iu&ictx=1&fir=Agh9rf5CUETQoM%253A%252CUWN TFeaMUY60dM%252C_&usg=__PZ_zyn4aGbIt9yHN-aaBulRoSPo%3D&sa=X&ved=2ahUKEwjUs9aFwsfbAhV1IDQIHS KDDeEQ9QEwA3oECAEQSw#imgrc=Agh9rf5CUETQoM:

Thanks, I spent some time and none of the videos I could find were close enough to what I have to help. I did find a comment from a individual that broke his door because he did not know how to get it to drop down . Unfortunately most of the posts on various forums asking for information on how to do it are from many years ago. Perhaps Monday I will call a GM dealer to see what they say, but have serious reservations about spending a lot of money on this vehicle.

This was my thought. Not having a fuel gauge is only an inconvenience, my concern is many have posted their problems kept getting worse.

From the original post: " My big question: Is it likely the BCM will continue to get worse until the car no longer runs?"

It does appear to be changing, today the fuel gauge had the low gas warning light and as I think back, the other day the A/C stopped working for about 20 minutesafter we opened the windows for a while it started cooling again.



ON EDIT:

I had to remove the screws holding the bottom hinge which allowed the door to open far enough to actually unhook it to remove the glove box.
Unplugging the bcm unit connectors had no effect. I did find a web site that lists refurbished for less than #300.00 (www.gmpartsgiant.com) but claims I must get
it programmed. I have read you can use a different bcm but mileage will be off - not sure

The bcm picture: BCM Module located on top of the glove box/

BCM Programming
 

I spent the $300 and got a new BCM, the fuel gauge seems to be working but I am unable to clear the "Security" light and the last time I started it, the air bag & wrench lights came on as well

I used the following procedure but it is not working, regardless of how long I wait the light remains steady on, I also tried just turning the ignition off after 10 minutes - same results:

30 Minute Learn Procedure
Turn ON the ignition, with the engine OFF.
Attempt to start the engine, then release the key to ON, vehicle will not start.
Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF.
Turn OFF the ignition, and wait 5 seconds.
Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes, the vehicle is now ready to relearn the Passlock™ Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.

I tried it several times, I found many references to using a used BCM but not much on a new one