Topic: Volt Gauge Troubleshooting

[Jeffy]

Seems my volt meter is dying, I'm hoping.  Currently it's reading 10-11-ish then it should be 12-13-ish.  Or on the YJ gauge just above the 12v hash mark.  At the battery is reads over 12v.  At the fuse box it reads over 12v.

The FSM says the gauge gets it's signal from the temp gauge.  So I'm hoping it's just the gauge is bad.  I haven't taken apart the dash to check the signal though.

Thoughts?

[sharpxmen]

Seems my volt meter is dying, I'm hoping.  Currently it's reading 10-11-ish then it should be 12-13-ish.  Or on the YJ gauge just above the 12v hash mark.  At the battery is reads over 12v.  At the fuse box it reads over 12v.

The FSM says the gauge gets it's signal from the temp gauge.  So I'm hoping it's just the gauge is bad.  I haven't taken apart the dash to check the signal though.

Thoughts?

what does it show with the engine running and what do you find with a digital voltmeter on the battery (same here with the engine running)?

[Jeffy]

The gauge reads 14 or there about.  Should be 13.6-13.8v.  I'll check it in a bit.

[sharpxmen]

The gauge reads 14 or there about.  Should be 13.6-13.8v.  I'll check it in a bit.

i think it's normal - it is really not meant to be much of an accurate reading other than to tell you if the alternator is charging or not. since you get the proper voltage shown with the engine running i don't think there's a wiring problem, mine behalves the same where with the engine stopped shows below (or very close) to 12v and between 13 and 14 with the engine running. Also makes a diff if you have for example the radio on (would show less since the alt is not charging).

[Jeffy]

i think it's normal - it is really not meant to be much of an accurate reading other than to tell you if the alternator is charging or not. since you get the proper voltage shown with the engine running i don't think there's a wiring problem, mine behalves the same where with the engine stopped shows below (or very close) to 12v and between 13 and 14 with the engine running. Also makes a diff if you have for example the radio on (would show less since the alt is not charging).

The only difference is that it was reading correct before.  I'll have to measure the voltage from the signal line to the gauge to be sure it's the gauge.

[sharpxmen]

The only difference is that it was reading correct before.  I'll have to measure the voltage from the signal line to the gauge to be sure it's the gauge.

the signal line is 12v switched by ignition - all of the gauges are powered by that and it is the reference for the voltmeter.

EDIT: can also be ground reference. you'll need to measure the voltage on the 2 screws that connect the printed circuit to the voltmeter gauge on the back of the gauge cluster - if that is correct on the digital vm and off on the gauge then it's the gauge, if it the same on both you have a bad contact or wire somewhere along the line (either 12v or ground).

[Jeffy]

Read my pins wrong.  I see the Ignition feed wire now.  Didn't have my digital gauge handy.  Hooked up the analog VOM and it said 12.6v when off and 14 and change when the engine's running.  Tracing it back to the PDM is fairly simple.  I'm probably 90% sure it's the gauge as the alternator doesn't sound like it's kicking in when the battery is low.  Also it shows a full charge when I put a charger on it.

Still gonna check the voltage at the gauge and then at the PDM.

[jfrabat]

On mine, if I turn the AC, the voltage reading goes all the way down  to like 11.5V or so (the faster the fan speed, the lower it gets).  Yet with the voltmeter, measured at the battery with the engine running, and running ALL the things I have hooked up to the Jeep (GPS, CB, 4 set of Aux Lights, Stereo blasting, interior light, eFan, etc.) the difference was something like 0.1V or so (dont remember the exact voltage, but I want to say 13.8 or so)...  I've never had an issue with the battery dying, so I just live with it.

[Jeffy]

High-amp items draw a lot of power.  I had just started to notice the difference in my gauge recently though.  Like when starting, the volts drop to 10v but that's normal.  When my fan turns on I see a drop in the voltage then it goes back a bit.  Also normal...  Probably too much water pouring down the backside of the dash causes the gauges to die.  My fuel gauge doesn't work unless the engine is running.  It used to work when the ignition was on before.  Also, it likes to get stuck at 1/4.  If I full it up, it will read E till I slosh it around a bit.  Them it may get stick at 1/4 or 1/2 till it breaks free.  I'm sure the gauge is bad since I know water poured directly onto it.  That's the problem with Jeeps.  They leak and the gauges rarely work.

[neale_rs]

Mine reads 2v high and shows a voltage drop when in reverse.  But the voltage is fine at the battery.

[Jeffy]

So I got around to tearing the dash apart for the umpteenth time.  The gauge is screwy.  The VOM was reading the right voltage from the harness.  It got me thinking about making a bracket for aftermarket gauges though.  Seems like you could make a template from some of the parts of the gauge cluster.  I took mine apart so I could take the individual gauge out.

[jfrabat]

So I got around to tearing the dash apart for the umpteenth time.  The gauge is screwy.  The VOM was reading the right voltage from the harness.  It got me thinking about making a bracket for aftermarket gauges though.  Seems like you could make a template from some of the parts of the gauge cluster.  I took mine apart so I could take the individual gauge out.

I've seen a dash sold for aftermarket gauges for the YJ; dont remember who made it or whol sold it (I think it was 4wd.com or Quadratec), but I am sure you can google that up.  It also allowed for 5 gauges instead of 4...

[sharpxmen]

I've seen a dash sold for aftermarket gauges for the YJ; dont remember who made it or whol sold it (I think it was 4wd.com or Quadratec), but I am sure you can google that up.  It also allowed for 5 gauges instead of 4...

i'm pretty sure it was made by autometer but i think (not sure) that it was discontinued or not available when I was looking for one. Could still be in stock at some of the resellers though.

[jfrabat]

i'm pretty sure it was made by autometer but i think (not sure) that it was discontinued or not available when I was looking for one. Could still be in stock at some of the resellers though.

This is the one I am talking about...

[sharpxmen]

This is the one I am talking about...

yeah, that's the one but i couldn't get it at the time (like 5 years ago) so i had to make my own.