Mechanics

CHEVY GAUGE CLUSTER....... STRANGE

1998 Chevrolet Blazer

Electrical problem
1998 Chevy Blazer 6 cyl Two Wheel Drive Automatic 130000 miles

I purchased a 98 blazer, 4dr, 2wd. Everything is in great condition.

I have to drive with an ignition test and lock (interlock) device in the vehicle. To test for breath samples.

I had the device installed this morning, it is wired into the ignition, the lights, and the horn and acts as a relay. If you have alcohol on your breath it will not allow you to start the car / the relay closes.

Before installation the car was fine, and so it was for a while after.

I was installing a new car stereo, so I had to start the car several times while I was testing wires for power to the stereo.

I noticed after I was finished and wanted to go for a drive that my gear indicator lights were out, the gas gauge was out, as were the speedometer and the odometer. The voltage and oil pressure gauges still work.

I read in a forum that a bad ignition switch will cause issues with the gauge cluster and was wondering if this would be the case? Perhaps a wiring problem with the interlock would cause this?

The interlock is also not functioning as it should. It asks for a test to start the vehicle but afterwards it shuts down (powers off) as if the car was off. But the car continues on as normal.

I need to take it to the interlock garage obviously, but would bad elevtrical contacts in the ignition switch cause these issues?5
AD
Avatar
Jault01
January 27, 2010.



Aint that a humdinger. Go back and undo the stereo install, and make sure that all the wiring is in good condition. Did you use scotch locks?
AD

Tiny
Scotty Dee
Jan 27, 2010.
Wow. Really? The stereo wiring could do that? No, I didnt use scotch locks. Never even heard of em! I'll go back and pull the stereo stuff out tomorrow, and start over. Come to think of it. The stereo clock and everything reset when I made the discovery too. And before hand, I didnt have that trouble.

Tiny
Jault01
Jan 27, 2010.
Ok, so today I removed the stereo. I didnt reconnect anything. Before I did that the stereo wasnt even powering up at all.

With everything disconected (stereo) the gauges still are not working except for the oil and voltage.

What next?

Tiny
Jault01
Jan 28, 2010.
I'm gonna take a stab at the chance you blew a fuse or two while restarting the car to attach wires, not a great idea. Check all fuses in the car and under the hood, tape all exposed wire ends, and yes, electrical discharges wether caused by short outs, or static discharge can ruin modules too! Ground straps should be worn by the installer of electronic equipment. If all was working b4 you installed the radio, then your attempt at radio installation is the cause. Sorry!

Merlin2021
Jan 28, 2010.
I actually replaced the harness to the wires as it was orifinally. I have everything taped off very well. The stereo works (well with a theft code) but it powers.

I've checked gauge and illumination fuses. They are fine. THe thing is that the gauges are not all non operational. The speed, odometer, trip (which are digital) temp, and gas are out while the oil and voltage are working. If it were a module wouldnt the entire gauge cluster be out?

Tiny
Jault01
Jan 28, 2010.
I; 'm beginning to think the instrument cluster has gone bad.

Tiny
Scotty Dee
Jan 28, 2010.
Best advice right now is to scan for " B" and " U" codes, generic scan tools cant do this, a high end tool like a snap on or GM Tech II will. If all was OK b4 you did the radio, then something was shorted, or power was removed.

Merlin2021
Jan 29, 2010.
Hey buddy I had the exact same problem to a tee and have solved the mystery. Your number 19 is your radio fuse and I guarentee it is blown. I have all of the same issues try this out and let me know. I just changed mine it and it fixed the problem the radio and cluster are connected to the same module and if the radio fuse is not working then the cluster will partially work.

Tiny
Geniusatw0rk
Feb 2, 2011.
That's what it was. I had just gotten the blazer and was not at all familiar with the way things were wired to the fuse box. Very simple wiring, I felt like such an idiot when I discovered that! Haha

Tiny
Jault01
Feb 2, 2011.

AD