Randy V

My voltage gauge (located on the instrument cluster) had stopped working awhile ago. It would work intermittently when I raised and lowered the pod, but now no longer responds to that.

So the thinking was it was a loose connection on the PCB plug.

How do I bench test the gauge to track down the problem?

There are 3 electrical connection stalks that come out of the gauge and seat into sockets on the PCB.

Should there be continuity between them?

I have a 9 volt battery with leads to use as a test rig - the gauge should move slightly when energized, but which connections are powered?

joejoe

Not sure if this is the same Randy, but on one of my '86.5's (we have had it since 1988) the temp gauge will peg past hot. For years all it took was a quick, sharp, tap on the pod and it would work again. As it turns out at one time ( I believe it was the first time I remove pod) I broke the 2 tangs that hold that part of harness to that side of cluster for temp gauge. If I reach under and push the harness onto cluster the gauge will read correct. Raising or lowering the pod will cause erratic readings. Especially if in lower most position (The harness is pulled most then). Pulled is not correct term, as the hardened tape "flexes' the connector.

Anyway, while looking at the cluster from beneath see if the harnesses have any binding on cluster. Especially the one behind voltage gauge.

928 at last

You sure there's nothing in the stickies for newbies???

928 at last

Just could not stop myself.....

OTR18WHEELER

I can add some confusion to this, I have had an issue with my voltage gauge also, which may be relevent
When my voltage gauge reads low, I bump the trip odo reset ****, and the voltage gauge will then register normal and slowly drop.(hold odo reset button in, and volt guage is flat, release the odo button and the volt needle jumps up, and hangs above 12v) Although after charging the battery several hours the volt gauge will read normal, and the bump of the odo reset does not change the reading.

The Fixer

You're on the right track Randy, the gauge is like any other and can be bench tested.

I would suspect the connector that energizes that gauge though if movement corrected the problem for a bit. Try the cleaning routine, but it could still be the printed circuit as it normally is.

I have a brand new printed circuit from the dealership for your car, i bought it to see the difference between the late (still available) and mine which is NLA.

It cannot be used in mine and i don't see buying an S4 or later car for a while.

If you find you need it, let me know. -Matt

Randy V

Thanks so far, guys.

I'm suspecting the gauge itself as I had previously resoldered the main leads to it, as some others had done to bring back a balky voltage gauge.

I'm hoping to get info on which main leads off the gauge should have power applied to get the needle to move.

jtrygstad

Randy,
How did this work out?

I have an intermittent volt meter, so I changed out the voltage regulator (hoping to solve some other issues). Voila, the meter started working again! The old regulator looked like crap and the brushes were well worn down.
Unfortunately, today it is back to resting below 10 volt again. So probably a connection problem.

On the bright side, the regulator replacement should at least help preserve the alternator.

Randy V

Never got it resolved.

My volt meter is inoperative at this time. I'm thinking it is a problem with the wire loom coming off the cluster, as the meter used to function intermittently when raising and lowering the pod.

jtrygstad

Maybe tonight when I drive home, I'll try to raise and lower the pod to see if I get a similar response.

AirtekHVAC

While bench testing (ok , liftbar testing) #30, my instruments would function erratically. I just pulled my pod for a refresh, and noticed that the right hand side PCB connector has no clip to keep it locked in place....I am pretty sure this is the cause of my erratic volt meter. The left side has the clip....I believe the PO (aka jack leg) has had the pod off before. I will be making a retainer of some kind when I reassemble.

(Btw, my connections were very corroded as well.)

jtrygstad

Raised the pod and banged it down. The voltmeter began working again (for awhile).

So, perhaps a loose ribbon cable connector on the right side? I really don't have the desire to remove the pod, but perhaps I should check it out. Could this be a reason for other rash warnings? For instance, I have been getting lots of brake pad warnings even though everything on the wheels are new including pad sensor wiring.

Chalkboss

It seems like dirty and loose connections can cause all these problems. Dwayne has a nice write up about pulling the pod and cleaning everything up. About the only thing I can add is to use Deoxit on the connections as well. I am getting some erratic readings from volt meter and fuel gauge jumping and a few bulbs out so I am going to yank the pod and deal with everything at once.