1999 BCM Problem
Thread Starter
Instructor
Joined: May 2001
Posts: 143
Likes: 0
From: Church Hill Tennessee
Cruise-In III Veteran
1999 BCM Problem
I bought my 99 new in July 1999 and have had very few problems with the car. It has been garage-kept since new and currently has 116,000 miles. About a week ago I drove the car and it started and ran just fine but the next day when I attempted to start the car the starter would not turn over. The battery voltage had been drained to 6.9 volts. I replaced the battery with a new Optima and after installing it I put a trickle charger on it to top off the charge. I checked the voltage on the new battery about two hours after connecting the trickle charger and the voltage was DOWN to 10.9 volts. While completing a static discharge test I discovered the instrument panel lights were illuminated with the ignition switch off. The static discharge rate was around 3.9 amps until the computers went to sleep and then it dropped to 1.5 amps. The instrument panel lights are powered by circuit 25 and that circuit also powers the body control module. After pulling the fuse for circuit 25 the parasitic draw dropped to 39 milliamps. I have never had a BCM apart so are there any replaceable parts in these BCMs and do they have to be reprogrammed after being disconnected from the car? Thanks in advance.
Melting Slicks
Joined: Sep 2008
Posts: 3,138
Likes: 802
From: Espanola New Mexico
Have you checked your dash lights dimmer switch? This switch can be turned full clockwise position past a fully on indent position. The BCM usually never draws excess current while off, unless water intrusion has happened due to clogged drain udders, and no replaceable components are inside, you either buy a new one or have your orginal repaired at a reputable repair shop that specializes in automotive electronics modules. A relearn procedure does have to be done if you replace your current BCM.
Tech Contributor
Joined: Jan 2007
Posts: 19,458
Likes: 1,165
From: Dyer, IN
I bought my 99 new in July 1999 and have had very few problems with the car. It has been garage-kept since new and currently has 116,000 miles. About a week ago I drove the car and it started and ran just fine but the next day when I attempted to start the car the starter would not turn over. The battery voltage had been drained to 6.9 volts. I replaced the battery with a new Optima and after installing it I put a trickle charger on it to top off the charge. I checked the voltage on the new battery about two hours after connecting the trickle charger and the voltage was DOWN to 10.9 volts. While completing a static discharge test I discovered the instrument panel lights were illuminated with the ignition switch off. The static discharge rate was around 3.9 amps until the computers went to sleep and then it dropped to 1.5 amps. The instrument panel lights are powered by circuit 25 and that circuit also powers the body control module. After pulling the fuse for circuit 25 the parasitic draw dropped to 39 milliamps. I have never had a BCM apart so are there any replaceable parts in these BCMs and do they have to be reprogrammed after being disconnected from the car? Thanks in advance.
By circuit 25, I assume you mean fuse 25. Circuits have numbers in the schematics....so just another small distinction.
Thread Starter
Instructor
Joined: May 2001
Posts: 143
Likes: 0
From: Church Hill Tennessee
Cruise-In III Veteran
An important distinction. A "static discharge" is a sudden release of static electricity. You are trouble shooting a "current draw" from your battery.
By circuit 25, I assume you mean fuse 25. Circuits have numbers in the schematics....so just another small distinction.
By circuit 25, I assume you mean fuse 25. Circuits have numbers in the schematics....so just another small distinction.
