my Volt Meter bounces down then back when i accelerate. The Alternator checks out fine and the battery is good.
Place a voltmeter in the truck attached to the cigarette lighter. watch what it does as you accelerate and the voltmeter in the car drops. If the voltmeter doesn’t drop, the gauge itself has issues. On a 16 year old truck, I’d say ignore it. If the voltmeter drops, too, I’d suspect the alternator’s drive belt is slipping, badly. Replace the belt and all tensioners. That assumes the alternator and battery are both good, as you say.
These trucks are notorious for bad gauges. The stepper motor (a little electric motor behind the actual gauges) goes bad, then you get erratic gauge readings for a while, and then eventually the gauge fails. If everything else checks out, suspect the gauge. Check out the voltmeter on my 05 Sierra. I’m deciding whether I want to replace the stepper motors, or buy a reman cluster from someone like Dorman.
Notice the gear shift display no longer functions either. It got dimmer and dimmer. Then disappeared. Due to poor soldering joints, from what I’ve researched.
It’s the actual motor that’s the problem
If you buy a re manufactured cluster it will need to get programmed. add $300. Replace the stepper motors and bulbs, $22 for parts in my case. You can drive without a cluster, I saw online places for motors and bulbs less than $100.
Those online places that specialize in rebuilding modules, cluster, etc. . . . if you send them your cluster, they’ll rebuild it with new motors, and no reprogramming is required
Some of these places even upgrade the cluster, by adding the automatic transmission fluid temperature gauge
Was talking about the PRNDL display, regarding the soldering joints.
Gauges going bad, agreed on the motors are the problem.
I have both. Lucky me!
Personally, the gauges would bother me more than the PRNDL
We have a few trucks at work that have the same problem with the PRNDL . . . I have no problems driving them. I just count the clicks, so to speak, and I know what position the shift lever is in. Not exactly rocket science
Agreed, it’s not an issue. I count the clicks as well. It’s just one of those things that bugs me. If the vehicle came with it, I want it to work. If it came with no AC, I prefer that over one that came with AC but it no longer works. I’m funny that way.
My truck, the gear display doesn’t work (no biggie), the volt meter doesn’t work (meh, kinda sucks), and the tach is starting to read low at times. The tach kinda bugs me the most for some reason. I may fix it this winter. I have to remind myself to pull a scrap GM cluster to solder / unsolder stepper motors. I’d prefer practicing so I don’t totally fubar my cluster.