electrical issue
 

Hey all;

I posted this a while back but wondering if there are fresh ideas. The fan blower runs continuously, the clock displays "0:00", the outside tempt guage stopped working, and my radio stopped working all in one shot. I put the car in storage with these issues and just brought it out so id like to know what to look for.

Thanks. '90 ZR1

Re: electrical issue
 

The generally accepted "fix" for the blower running constantly is the BCM (blower control module) on top of the evaporator case BUT I don't recall ever having anyone report the other related failures occurring simultaneously. I've never actually understood exactly what takes the BCM out, the couple times I've seen it, it just happens. Shut the car off walk away and wonder what the noise is.


You haven't mentioned anything other than just putting it away in that condition. Have you checked the related fuses? There's an in-line fuse near the blower that's often talked about but I've actually never seen it fail.

With the components you've mentioned down I'd check radio, CTSY, AC fuses in the panel and the in-line at/near the BCM. Unplug the 4 wire connector to the BCM first maybe, then check all of components again after confirming the fuses are good.

I assumed this is a C68 car.

I'd probably disconnect the negative cable for a while to let the CCM, the programmer and all of the electronics to reset themselves. This I believe would be right after confirming that the fuses are all good. Is anything on the AC control flashing indicating an error?

Re: electrical issue
 

Yes i brought it to my garage and they checked all the basics but i was referred to an electrical shop. Just didnt have time to get it there before the weather turned last year. Thanks, im not mechanically inclined myself so ill pass these suggestions along to the specialists.

Re: electrical issue
 

Checking the fuses and removing the negative cable I wouldn't think should require a shop. If fuses are good, and the disconnect of the negative cable fails to reset all of the electronics and the issues are still present then the shop.

Re: electrical issue
 

So turns out the Bose is pooched on the car and when they pulled it out, looks like it was causing an issue with the climate control and outside tempt gauge. So now the climate and tempt are fine, just gotta replace the Bose or rebuild it.

Thanks all for your help.

Re: electrical issue
 

Real wierd however thanks for this follow-up. It may help the next guy. :cheers:

Re: electrical issue
 

My 91 L98 acted that way when the CDM pooped out. So pulling the Bose head unit would isolate the CDM. It's a real pi$$er to replace - good luck. And Dr. Don rebuilds 'em.