1991 T-10 Blazer 4.3L z automatic

New Alternator and battery has been installed. Under no load conditions-just the engine running the voltage across the battery is 13.65v. This seems a little low to me.

As electrical conponents are turned on voltage drops significantly. When everything is turned on the voltage across the battery is 12.33v. It is charging the battery because when I disconnect the terminals the truck still runs.

The lights seem to be the biggest drain however the ac blower is a large drain as well.

The instrumentation and courtesy lights are a large drain as well. I can watch my internal volt meter move as I adjust these. recently I have kept my instrument lights off.

I can watch my gas gauge and temp gauge move as well whenever I adjust those instrument lights OR turn on & off other devices such as lights, AC blower, wipers...etc.

I have thought of cleaning every ground I can find. Would that help?? I am almost positive I do not have a short because my battery has never ran down.

HAS ANYONE EVERY HAD THIS TYPE OF PROBLEM WITH A 1ST GENERATION?

Any enlightenment would be greatly appreciated. Thanks!

 

Check over all of your main power and ground connections. Sounds like your alternator is not putting out the proper voltage. It should be 14V-14.5V at idle with minimal load.

 

Thanks that's what I was thinking as well.

 

Man O Man..don't know where to begin

Cleaned every ground I could find. Increased voltage from alternator to exactly 14.03V

Seemed to do pretty good under load decreasing to 13.71v fully loaded.

Today all hell broke loose.

When headlights are turned on the instrument panel goes dead....everything speedometer, oil psi, voltmeter, gas gauge temp.

when courtesy lights are turned on all goes back to normal IF the door is open....close the door and goes dead again.

I realize that the instrumentation lights and courtesy are related circuitry but damned if I can find the problem.

Took instrument cluster out couldnot find anything unusual.
Light switch and dimmer/instrument lights are new.

Unhooked my stereo to make sure it was not the problem....it doesnot work as well now with the other problem.

Anyone have any ideas??

 

This is starting to sound like the ignition switch is not functioning properly and power is back feeding through other systems...

 

I can get a switch for about 13 bucks at Advance. I'll try that but I am not positive that will cure it.

Just a thought - - > I have always had a minor problem with the turn signal lever...when setting to turn to the right the wiper would cycle 1 time. Wiondering if the problem may be inside the steering column perhaps??? Any thoughts?

 

The wiper cycling with the turn signal is usually a problem with the multifunction switch (turn signal lever).

 

Gotterfixed!

Simply ran another ground pigtailing off the black wire from the connector where the instrument cluster plugs in.

Everything works..Now I just have to put it all back together!

 

good job!