Gauges not working

[454k30]

I am currently working on an 82 k5 whose gauges are not working. Now I can chock the speedo malfunction up to a busted cable but the other four (fuel, oil pres, volt, temp) do not function either. All of the lights on the gauge panel work. Where do I start troubleshooting this?

 

[jhellwig]

Fuse panel. There should be a fuse for the cluster.

 

[454k30]

I need to get a multi-meter. The fuse is good, where does power come from for that system? Is it from the ignition relay?

 

[throttleissues]

So, Tom, are you saying there's no power to the fuse when the key is on?

 

[454k30]

Thats what I going to find out tomorrow when I get ahold of a test light. My feeling is that no power is getting to the fuse as I put several known good fuses in there and the gauges never powered up.

 

[454k30]

Well a bad fuse was the culprit behind several other electrical mysteries in that truck. Turns out that it was mostly bad gauges. After swapping them with known good ones it turns out that the volt, temp, and oil pres gauge are all bad. Also the oil pres sending unit is shot. Luckily the fuel gauge works, but the sender in the tank is bad. Also I learned that a fuse tester is a good tool! Amazing how a fuse can look good and actually be blown.

 

[noJeepshere]

There must have been somekind of powerspike to ruin all the gauges like that, I've heard of one or two, but all of them? Hmm...

 

[throttleissues]

Next test, voltage regulator! Seriously, check the charge voltage @ idle, sustained high RPM and quick revs. Voltage should be in the 13s. Anything even spiking above 14.5-15.0 is really bad for parts. Just to be sure the problem that killed the guages isn't still there.

 

[Mike D]

Remove the instrument cluster. Check the copper receptical on the circuit board where you unplug it. Over time both the male and female connections get corroded and don't pass on the power. Get a wiring schematic of your instrument panel and check for voltage at the the male plug and continuity between the female connector and guage. Heat and age really affect the flexible circuit board.

 

[454k30]

I did that when I had the whole cluster pulled out. Corrosion was certainly present. If you guys could've seen the wiring spaghetti that was behind the dash, a short or spike is certainly a possibility. Of course the other possibility is that over time they just failed one at a time and the PO never did anything about it because the fuel gauge is still good but the level sender is shot.