I seem to be having some strange electrical problems on an 88 Chevy
Silverado pickup. The most troublesome one being the heater/AC control
unit. It flickers and turns on and off, and is not working much at all
now. The power locks stopped working and the wipers sometimes will not
shut off. I thought maybe the heater/AC control unit was gone, so I
got a rebuilt unit and put it in. Same problem, it flickers, and turns
on and off, etc. Has anybody had this problem? or have any idea what
could be causing it?
If it's the same problem I had with my 92 then its a bad connector. I
actually had smoke but didn't catch fire. Amazing that the fuse did not
blow. Anyway the connector I am talking about is behind the heater control
unit. Pull out the heater control and follow the wiring harness into the
dash, Its been a while but I believe the connector is gray or white, a six
pin Molex connector. Pull it apart and see if it is burnt to a crisp. If I
remember correctly the ground and pwr pins are right next to each other.
When I was working on mine I let the control hang and went moving wires and
I could make the unit turn on and off.
Behind the glove box, next to the blower should be the power connector
MasterMech is talking about.
They usually melt when the pins loose their spring. A RatShack Molex connector
is a good replacement
As for the others, they may not be related. Did they all act up at once?
I checked all the connectors behind the glove box. They all looked clean with
no evidence of any shorts.
Are you saying to just run a grounding wire from the battery to somewhere on
the frame? Have you seen this cause this type of problem before?
Is there a way to check if there is a ground to frame problem with a
There should be a wire from the negative terminal to the fender and
also a braided cable from the engine block to the firewall These are
the ground paths for all circuits that use "Chassis" ground as opposed
to an actual ground wire.
firstname.lastname@example.org (Paul Girouard) wrote in message
Thanks for the info. I'll pull out the glove box tonight and take a look.
The electrical problems didn't happen all at once, so maybe they're not
related. The power locks were working, then started working intermittently,
then stopped working altogether.
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