Need help with my trefeo
 

Okay so I have a 1988 Oldsmobile toronado trefeo I got the car awhile ago from my dad and he was the only owner. Anyways I am having that common problem of the dash and interior lights going on and off or working off and on. I have know I need to replace something but when I look it up I hear to change the CPS (central power supply, PCM (power control module),and bcm (body control module) which one is the one I need to replace or are they all the same thing just different names. Also if anyone knows of any good places online that don't charge an arm and leg that would help.
Well that was the first problem I am also in need of a window regulator in this case I have found a wrecking yard in my town that has tons of Cadillacs I was wondering which ones are the same as mine when I looked at them the 88 el dorado appered to be the best match. Any help would be great thanks all.

Eldorado and buick riviera are excellent matches.. basically all the same mechanicals except the cadillac engine. The BCM, PCM and CPS are all separate units.. the CPS is under the console below the tape player. The BCM if i remember right is either under the dash or in the trunk. the ECM i think is under the dash.. been a loooong time since I've ripped apart a trofeo.. You could check for intermittently grounding wires by wiggling as much wiring harness as you can. Had a bizzare climate control issue in my 89 trofeo that was a wire chaffed thru on to the dash mounting bracket. Do yourself a HUUGE favor and invest in a factory service manual. It will be the best money you ever spent.. got one coming today for my 92 trofeo that i'm refurbishing.

Thanks a lot I appreciate your help

Any time.. Now that i'm ultra knee deep in refurbishing my 92, I'm getting back into things and alot of info is coming back.. also got a 92 factory manual the other day. So if you have other questions, I can look them up for ya.