Body Control Computer

knightrider2000 · January 21, 2004

Thinking of changing the BCM in my 1999 to a later model one, so i can have the automatic door unlock, and option to turn the automatic headlights off. What year should i go up to? would one out of a 2002 work in my truck? What year did they make it so that when gearshift went to park that the doors would unlock? (thats what i am wanting. Thanks

Matt G.

GnatGoSplat · January 21, 2004

2000-2002.

Although my 99 with a 00 BCM, it only unlocks when you pull the key out of the ignition. I don't remember there being a setting to work with the gearshift.

J-rod · January 21, 2004

Mine unlocks when ya go to park ... 2002 here though.

seadoons · January 21, 2004

My doors lock when you put it in reverse or drive and then unlock when going into park. Kind of a pain in the ass when it goes to park - I am not always getting out of my truck when I put it in park. I wish they would unlock when I turn the truck off.

2002 here

GnatGoSplat · January 21, 2004

I checked the online owner's manuals on MyGMLink.

Looks like they changed in 2002.

00-01 lock when the truck reaches 15mph, and unlock when the key is pulled out of the ignition.

02 trucks with manual transmission still work like 00-01.

Not realy exciting info, but interesting anyway.

knightrider2000 · January 22, 2004

did you do a password learn feature or anything after you installed the new BCM?? also i am curious, my trk has foglights, if i change BCM's does it need to come from a truck with them installed??

Matt G.

Shaners · January 22, 2004

The '02 models had several "lock" options on them that the previous years didn't have.

GnatGoSplat · January 22, 2004

Yes, you do have to do a password learn feature.

Basically, you just crank the truck and leave it on. It won't start, but will blink SECURITY. Wait till it finally stops (may take 10-minutes), then shut off the truck for something like 10-seconds, then repeat. The password is learned when the truck finally starts. It's been awhile so I don't exactly remember the procedure anymore, you might do a search as this subject has been mentioned a few times.

00-01 actually has as many lock options as 02, only what triggers locking and unlocking is different. For all those years, there are 4 possible settings. 99 is the year that has no options.

ness5575 · January 22, 2004

GGS is right. '00 and up have the programmable locks. that is the first thing i did when i got my '00 home - change the locks. i hated how the locks worked on my '99...

99GMCZ71 · January 23, 2004

My BCM came out of a 2000. It locks when you hit about 15 mph, and unlocks when you pull the key out of the ignition. That's the way I like it. I usually eat lunch in my truck, and i don't like the doors unlocking when you put it in park, because i stay in the truck. It took 4 tries for the BCM to work after using the 10 minute crank and learn security procedure.

GnatGoSplat · January 23, 2004

My BCM came out of a 2000. It locks when you hit about 15 mph, and unlocks when you pull the key out of the ignition. That's the way I like it. I usually eat lunch in my truck, and i don't like the doors unlocking when you put it in park, because i stay in the truck. It took 4 tries for the BCM to work after using the 10 minute crank and learn security procedure.

Heheh, I eat lunch in my truck too, and I also like it that way.