Headlight and Interior light Issues

So that solved your problem Matt? My headlights and interior lights work, its my dash lights and perimeter lights that won't come on. Did you have to use one out of a 96 Riv or did you pull one out of another Buick?

BMD wrote:

So that solved your problem Matt? My headlights and interior lights work, its my dash lights and perimeter lights that won't come on. Did you have to use one out of a 96 Riv or did you pull one out of another Buick?

My problem wasn't exactly like yours but there are some overlaps between our issues. It did indeed solve my problem, and I got mine from another 1996 Riviera. I believe the module is sensitive to certain model years (i.e. due DRL's appearing in 97-99 among other changes), and I do not believe it is interchangeable with other Buick models. Might be worth running the part number however.

I wonder if the LCM from other model year Rivs' will work for me because in Canada, DRLs have been standard for many years. I think it was standard on my Riv.

BMD wrote:

I wonder if the LCM from other model year Rivs' will work for me because in Canada, DRLs have been standard for many years. I think it was standard on my Riv.

It may very well work, but that was the only change that I know of for sure. There may be other lesser-known internal changes that could cause problems. Like I said the only way to know is to obtain the part number

BMD wrote:

I wonder if the LCM from other model year Rivs' will work for me because in Canada, DRLs have been standard for many years. I think it was standard on my Riv.

NO!! (Perhaps we should have a different color for owners of Canadian cars... )

BMD, even though it seems we were just talking "aboot" this on another thread only a few days ago, because the Search function on this host is such a picky little shit, I can't find it...

However, we found that the Canadian Rivieras had the same schematic as the American Auroras... They used the low-beam-thru-a-resistor design, instead of the hi-beams-running-in-series-like-the-cooling-fans design.

HEY SCOTT!!! Can you find that damned thread? (He confirmed that it was the same schematic, and wiring colors, and LCM, etc...) Regardless, if you check the Olds side of your FSM you may find that an Aurora can provide a donor module.

Unfortunately, I am not quite as learned as some of you when it comes to studying the FSM, wether it written in English or Canadian . Can you guys confirm if the LCM from an Aurora will work because there is no Riv at my nearest pick and pull but there are a couple of Auroras!

Until AA or Abaddon come to the rescue, you could always pull your LCM and take it with you to the wrecking yard...

PS - Is your FSM Amurican or Canadien?

Hmmmm, don't have it handy, I assumed the pinkish beige two book FSM was all there was for 96.

BMD wrote:

Hmmmm, don't have it handy, I assumed the pinkish beige two book FSM was all there was for 96.

I honestly didn't know, but from what you describe it does sound like the U.S. version...
However, if you look at your resistor and headlight wires, I think you'll find that they match the Aurora schematic.

Thanks for your responses Mark. Do you know if I will I still have the use of the headlights, signal and brake lights if I remove the LCM to bring with me to the salvage yard for comparison?

BMD wrote:

Thanks for your responses Mark. Do you know if I will I still have the use of the headlights, signal and brake lights if I remove the LCM to bring with me to the salvage yard for comparison?

I believe the brake and signal lights will still work as I recall driving to the junkyard with the module already uninstalled. Just don't go at night! Can you receive a ticket in Canada for driving without DRLs?

You bet!!!

BMD wrote:

You bet!!!

Maybe the brights will still work Thats what I had to do when my LCM initially failed and I was driving home from work at 10 pm...

Which one is the LCM, the one on the inside of the white plastic ( closest to the brake pedal) or outside, closest to the Fender?

This is the number on the box closest to the inside!

BMD wrote:

Which one is the LCM, the one on the inside of the white plastic ( closest to the brake pedal) or outside, closest to the Fender?

This is the number on the box closest to the inside!

It's the inside one. That part number shows up for Auroras too FYI.

Hmmmm, this pic in the FSM looks like its the outside box,

but you've done this before so I'll take your word for it ! I hope your right about the P/N, because I called five salvage yards around here aswell as Morads, and none have an LCM for a 96 Riv. So I will go pick up one from an Aurora and hope it does the trick!

BMD wrote:

Hmmmm, this pic in the FSM looks like its the outside box,

but you've done this before so I'll take your word for it ! I hope your right about the P/N, because I called five salvage yards around here aswell as Morads, and none have an LCM for a 96 Riv. So I will go pick up one from an Aurora and hope it does the trick!

Well I cannot exactly remember which one it is from doing the removal myself (I actually stripped the BCM and LCM from the salvage Riv) so I am kind of mixed up, however when I ran that part number on this site it showed up as the lamp module... http://www.gmpartshouseusa.com/

Mechanical Catalog
Item Number MSRP Core Price Price
25638307 $344.67 $0.00 $255.40
Electrical - Chassis electrical - Headlamps - Sentinel module
Sentinel module, aurora 1996
Add to Cart Contact Us

I really cant remember which side it is though, I do remember studying that picture though.

OK Matt, thanks for all you help, I'll check it out tommorrow!

I've got it! From the Service Manual....



1. C202
2. Lamp Control Module (LCM)
3. Body Control Module (MALL)
4. Starter Enable Relay

Looks like it is the inside one.

What page is that on, I must have missed it?!

Edit: I see its from a 98 FSM!

BMD wrote:

What page is that on, I must have missed it?!

I am not sure I am getting it from online, however it is identical to the picture you posted on the previous page. That picture is taken from the 1998 FSM however but I dont know why they would have switched sides between 1996 and 1998? Sorry I can't get a concrete image for 1996, the LCM repair wont show up when i look up that year.

BMD wrote:

What page is that on, I must have missed it?!

Edit: I see its from a 98 FSM!

Although its from 1998, it is the same picture you posted before



This came from a 1996 FSM correct?

The pic I posted is from the 96 FSM, but the pic you posted looks like what I see under the dash?

From what I can tell the two FSM pictures we posted are identical (save for labeling style) and indicate that the LCM lies on the inner face of the bracket. When referring to your picture I am talking about the one with yellow highlighting.

The same box labelled LCM in my pic is labelled BCM in your pic.