relay turning on and off

[skull1]

on my 89 deville the power accessories relay clicks on and off when it does the radio,windows and instrument panel lights all work with the ignition switch turned off as long as the relay is turning on and off, i have to pull it out to make it stop if any one could help i would greatly appreciate it

[custom-uniforms]

I had a 90 Fleetwood that had the exact same problem.
It turned out to be one of the cars many computers.
A good mechanic should know which of the computers causes this.
This is a standard problem that many mechanics do know about.
I would advise going to a wrecker to get the computer for $20.00
rather than paying over $1,000.00 from a dealer.
After you know the part you are looking for try http://car-part.com/
and call around.

[skull1]

Originally Posted by custom-uniforms

I had a 90 Fleetwood that had the exact same problem.
It turned out to be one of the cars many computers.
A good mechanic should know which of the computers causes this.
This is a standard problem that many mechanics do know about.
I would advise going to a wrecker to get the computer for $20.00
rather than paying over $1,000.00 from a dealer.
After you know the part you are looking for try http://car-part.com/
and call around.

could it be the body control module? i can unplug it and make all the power accessories stop working that the relay opperates and thanks for the info

[custom-uniforms]

Yes, the BCM rings a bell.
My mechanic got me one for under $100.00
but a wrecker would be much less.

[skull1]

Originally Posted by custom-uniforms

Yes, the BCM rings a bell.
My mechanic got me one for under $100.00
but a wrecker would be much less.

yes i changed the bcm and fixed the problem thanks for the help very much

[nate95116]

Where is the BCM located? I have an 88 Fleetwood that turns on the radiator cooling fans for an instance, then they won't come back on...unless i turn on the AC. Any other ideas if not the BCM?

[custom-uniforms]

The BCM computer turns on the fans for a moment at startup as a onboard diagnosis that the fans are working. The fans will not turn on again until the coolant gets so hot to require cooling. In winter the fans might not come on as often as summer. If the car does not overheat and does not give dash board coolant temperature warnings everything might be normal. I'm not sure why the fans go on when you put on the A/C. Maybe Cadillac figures if it's hot enough for you to put on the A/C putting the fans on would not hurt. Maybe they figure the extra electrical load might overheat the motor so the fans are turned on or maybe the fans keep the A/C compressor from overheating. If the car does not overheat or say stop engine, then why worry about it.
Does the car overheat ?

[skull1]

on most vehicles the cooling fan or fans come on when the a/c is turned on because it puts a load on the engine and like custom-uniforms said they will not come on until they are required to