Electrical Issue

[HamiltonCR]

Hello, I have a 99 Buick Park Ave. A few weeks ago most electrical systems died,
The wiper blades, power windows, instrument cluster, radio, HVAC, all just stopped working but yet they have power going to them and some have some functions still operable.
Power windows will work with ignition in on position but not when car is running, only thing on radio that works is the recall button, instrument cluster gauges jump around till they finally bottom out, display hud is inop along with the gear indicator.
The BCM has been replaced and the fuses have been checked. I also cannot find a short within the wiring.

Any ideas would be highly appreciated, thank you for your time.

 

[Spriteman]

Was the EPROM from the old BCM switched to the new BCM? or was the new BCM flashed with your cars RPO settings? This can cause a no-crank or other system malfunctions.

 

[HamiltonCR]

The BCM came from another 99 Park ave, and when I installed it there was no change, the car still starts and runs with headlights and dashlights, but that all that works correctly.

From what I have read that the BCM didn't have to be flashed at a dealer, supposedly just plug in and turn the ignition a time or two to the on position to get the computer to identify it. Which i'm starting to wonder if it does need to be flashed in order to be linked to the ecm.

 

[fm9572]

I've had some success with adding a redundant lead to the fuse center under the hood. I would also change all of the old fuses out. They can get corroded like battery cable leads, and cause some of the problem. You can find pictures of what I've done in this thread. http://buickforums.com/forums/showthread.php?t=33323

So far, since I've done this, I haven't had the problems like I was having. Good luck to you.

 

[HamiltonCR]

To those who took the time to help me, I would like to that you for the help on this matter. This problem has been resolved

The problem was 1 of the 3 wires from the starter was not fully secured which caused a power loss to the under dash fuse box.

To think something so simple could cause so much frustration

 

[pila80]

Good to hear you have it solved. Sometimes ya can't see the woods.....the trees are in the way ..

 

[fm9572]

Could you tell us which wire it was you secured? I've been having the same problems to a different degree with some of my systems. Even with all of the other electrical work I've done, it still has issues with the windows and the door locks after it's been driven in around town driving.

 

[HamiltonCR]

After I got it back from the auto shop with only them telling me it was the BCM, I looked into the problem myself.
The starter on my car has 3 post on it, the large post is for the main power cable which was not fully secured the nut had come loose. The front smaller post was fine, but the other small post behind the 2 had a wire on it that had no nut securing it.

So i tightend the main power cable and secured the small post in the back with another nut, after I done that the car still had the issue so I went back to the under dashboard fuse panel and found the run/accessory fuse was blown which it was not before hand.
I put in a new fuse and everything came back, only thing I can think of is when I tightend the wire on the starter it must have surged the fuse causing it to blow. Hope this can help someone else before they rip their car apart like I did.

Goodluck to you

 

[fm9572]

Thanks. I'll look into it in the morning.

 

[fm9572]

I think my problem may be the circuit breaker. I'm planning on getting one the next time I go to town.