BCM in a '94 Century?

['84 6000]

I had the glove box out of the Century today to unhook the power antenna and noticed what looks like a second ECM right on top of the actual one. It has one plug with a bunch of 14ga. wires and another with smaller 16ga. wires that looks more like the usual ecm plugs. Anyone know what that guy is for? I need to unhook my ABS controller and Airbag controller so I figured it was worth asking.

[Century7667]

A second one? I only saw a single one on my '95. That should be interesting...

Ken T.

[Jr's3800]

You sure its not a Keyless Entry Module?

['84 6000]

The car does have it, so thats possible. If I wasn't on dial up I'd post a pic. It is stacked right above the ecm, same style case on a slightly smaller scale. Figured I would ask as I'm looking for the air bag control module too. The horn buttons quit so the steering wheel and air bag are coming out.

[Century7667]

You sure its not a Keyless Entry Module?

I thought that module was in the trunk? ...or is that just the transceiver?

Ken T.

['84 6000]

Damn cars...

[Prospeeder]

isnt that the BCM? controls the door locks that lock when in drive and unlock in park, and the fading interior lights, and the security lighting.

['84 6000]

Now that you mention that... I'm going to attempt to unhook it and see where that goes. I want to punch babies every time the doors lock on their own, the unlock button on the driver's side doesn't work and it won't unlock the doors until I reach across the car and do it or I shut it off.

[Century7667]

Now that you mention that... I'm going to attempt to unhook it and see where that goes. I want to punch babies every time the doors lock on their own, the unlock button on the driver's side doesn't work and it won't unlock the doors until I reach across the car and do it or I shut it off.

There's a lock fuse that you can pull to disable that. My '96 Century would lock the doors automatically when you put it in drive. The owners manual detailed which fuse to pull to disable it. The fuse's sole purpose is the lock circuit; pulling it harms nothing.

Ken T.

['84 6000]

I pulled it on mine, they unlocked when I pulled it but continue to lock when it is put into gear.

[SCREECH]

I had the glove box out of the Century today...and noticed what looks like a second ECM right on top of the actual one. Anyone know what that guy is for? I need to unhook my ABS controller and Airbag controller so I figured it was worth asking...It is stacked right above the ecm, same style case on a slightly smaller scale.

isnt that the BCM? controls the door locks that lock when in drive and unlock in park, and the fading interior lights, and the security lighting.
That second module is indeed the BCM - but that's Brake Control Module. It's the brains for the ABS. I pulled that brown plastic bracket and ECM/BCM out of a '94 Century I scrapped a while back to install into my '89 Ciera when I add ABS. As to why a '95 wouldn't have it, as Ken mentioned his didn't, they may have mounted it elsewhere perhaps, but I don't know for certain. I have '95 A-body factory manuals, but haven't looked at them. I'll have to do that, because now I'M curious as to whether this is something they changed. In '96 it's going to be a totally different ball of wax in there I'd expect since they went to an OBD-II computer.


You sure its not a Keyless Entry Module?

I thought that module was in the trunk? ...or is that just the transceiver?
The keyless entry module would indeed be in the trunk, on the top of left rear wheel housing, accessed by pulling back the felt lining.

[SCREECH]

Here's some pics I took when I was parting my '94 way back when...

http://screech.ws/miscpics/94century_parts/ecm-abs01.jpg

http://screech.ws/miscpics/94century_parts/ecm-abs02.jpg

http://screech.ws/miscpics/94century_parts/ecm-abs03.jpg

http://screech.ws/miscpics/94century_parts/ecm-abs04.jpg

['84 6000]

Thats for sure the one, I figured it out a couple weeks ago by accident but forgot to post. I have it all unhooked, I was hoping the light would go out but, of course that would be far too easy... In some years of Cavalier they mounted the abs controller in the cowl, the plugs stick through into the engine bay, possibly the same with our cars? Now to figure out how to disable the automatic locks and auto headlamps/DRLs... Any ideas there screech?

[SCREECH]

Thats for sure the one...I have it all unhooked, I was hoping the light would go out but, of course that would be far too easy... In some years of Cavalier they mounted the abs controller in the cowl, the plugs stick through into the engine bay, possibly the same with our cars?
Pardon me...ya lost me there...the second computer mounted on that bracket IS the ABS controller. Re-reading your quoted statement, am I correct in assuming you were suggesting the similarity to the J-bodies because you suspect that there is still another controller that has yet to be disconnected due to the ever-present illuminated dash light? If that's the case, then rest assured, there's not. But what there IS is a shorting bar. It's a bar built into one of the connectors for the ABS controller (or BCM) that completes a circuit when the plug is UNPLUGGED from the controller. It is designed such that the ABS system cannot easily be circumvented without the dash light indicating a problem. I had the same issue in a '96 Regal I used to have. I put a sport wheel on it, so I ended up having to disconnect the plug from the controller (located under the passenger seat) and put a piece of cardboard into the connector to keep the shorting bar from lighting the ABS light.


Now to figure out how to disable the automatic locks and auto headlamps/DRLs... Any ideas there screech?
I'll have to check the factory service manual and get back to you. I'll hopefully have time tomorrow evening. I'll let you know as soon as I can.

['84 6000]

I was referring to the newer cars not having it in the same location as the '94s, possibly in the cowl like the cavaliers had? As for the shorting bar, that answers the question about the light. I will have to take a look at the plugs and see what I can see there.

On the lights, I have been wanting to stop at the dealer and get the diagrams copied but they never seem to be able to find the books. go figure. If you could that would be great though.

[SCREECH]

1994 Daytime Running Lights factory service manual info:
http://screech.ws/miscpics/82-96a/94_drl/

Looks like you can simply unplug your DRL module, but in a Century you'll lose your BRAKE light when the parking brake is set though - the ABS and low fluid warnings will still operate normally. Your HIGH BEAM ON indicator is also routed through the DRL module on the Century.

1996 EBCM and PCM placement:
http://screech.ws/miscpics/82-96a/96_ebcm_pcm/

Looks like they're in the same spot, but the EBCM is mounted a little higher and is now horizontal. They've obviously used a different type of bracket altogether, but I'm sure they're likely interchangeable as far as bolting an OBD-II bracket into an earlier A-body. GOOD TO KNOW!!! ;)

['84 6000]

Thank you Sir! That is exactly what I was looking for. Now to see what I can do one day when it warms up.