Voltage regulator gauge

[cybercusp]

This morning I went to take the car out and the voltage gauge seemed dead. The car runs and starts fine and it was working yesterday. Any thoughts? 14885

[Ron]

If the Temp gauge is working, power for the Volt Gauge is on the "circuit board" (shared fuse). If the Left Turn Signal or High Beam Indicator is working Ground for the Volt Gauge is at the "circuit board". The Volt Gauge only has the two connections, so if you have both of the above, you have a bad gauge or bad connection(s) to it:

1. Slap the top of the Binnicle with the Key On a few times.
2. Disconnect and reconnect the battery with the Key On, everything else off.
3. Wiggle shake.
4. Bite the bullet....

[WelmoedJ]

+1
If the battery light is off after the engine is running, it must be something in the instrumentspanel.
Try and find Voltage (you need to take the binnacle off to get at the meter connections.

You could try and check the big connector to the instruments panel for Voltage.
If it's there (the green wire, could be present more than once and also present at fuse 13) it must be higher up the line.

[DMCMW Dave]

Turn key on.
Slap the side of the binnacle with your open hand. Maybe twice. Needle will unstick.

Clean your grounds and bulkhead connection.
Don't turn the engine off with everything turned on, especially the air conditioner.

[jawn101]

...
Don't turn the engine off with everything turned on, especially the air conditioner.

Now that's got my interest... why's this a bad idea?

[cybercusp]

Thanks for the responses. It's unstuck..took a wrong turn down a bumpy brick road and it sprang back to 13+ volts. I'm sure it won't be the last time. Going to take apart the binnacle and clean the contacts.

[kings1527]

Nice to hear you got it resolved.

I'm having a similar issue that's definitely along the same lines as this.

I just installed the new DMCH 140A alternator and my gauge reads around 12-12.5V; probably what my battery is and I'm worried that the alternator isn't charging...or the gauge is wrong.

I'm going to check the power with a multimeter at the battery cables with the car off to get a baseline reading and then with the car on and that'll definitely give me my answer. As I was told, 13.5V is a minimum and 14.2V is optimal.

If the gauge is wrong and the alternator is good (which I'm expecting...and hoping), I'm guessing it's a ground or fuse issue?

1) Check fuse #5
2) Check ground to the right of the radio under the center console
3) Check the bulkhead connectors and I'll put some dielectric grease on the contacts just to be preventive.
4) Check the speed nuts connecting the gauge to the paper on the cluster
5) Maybe add an additional ground from the engine to transmission? So the main would go battery to engine, then engine to transmission. I've heard good things about that on multiple levels.
6) Clean contacts on the two sets of bundled wires and clean them with a wire brush on a Dremel

Any other ideas?

Alex
6575

[DMCMW Dave]

Now that's got my interest... why's this a bad idea?

If the grounds are flaky sometimes you can get a reverse current from a collapsing coil field that drives the meter backwards. Apparently the meter has no mechanical stop and it gets into a position where it sticks.

[DMCMW Dave]

1) Check fuse #5

Any other ideas?

Alex
6575

I have seen a dirty fuse #5 cause the voltmeter to read low. A bad meter would be pretty rare, and obviously a resistance anywhere else in the circuit (i.e. grounds) could cause the same low reading.

[jawn101]

If the grounds are flaky sometimes you can get a reverse current from a collapsing coil field that drives the meter backwards. Apparently the meter has no mechanical stop and it gets into a position where it sticks.

Oh, interesting. Yet another argument to spend as much time as it takes on those grounds, right? :)

[Ron]

If the grounds are flaky sometimes you can get a reverse current from a collapsing coil field that drives the meter backwards. Apparently the meter has no mechanical stop and it gets into a position where it sticks.
+1

....remember when your brother/sister used to suddenly let go of the tug-of-war rope LOL

[Bitsyncmaster]

If the grounds are flaky sometimes you can get a reverse current from a collapsing coil field that drives the meter backwards. Apparently the meter has no mechanical stop and it gets into a position where it sticks.

Same goes for the fuel gauge. Mine got stuck way past the empty mark and I had to pull out the gauge and move it by hand.

[Elvis]

Nice to hear you got it resolved.


5) Maybe add an additional ground from the engine to transmission? So the main would go battery to engine, then engine to transmission. I've heard good things about that on multiple levels.
6) Clean contacts on the two sets of bundled wires and clean them with a wire brush on a Dremel

Any other ideas?

Alex
6575
...say hello from sister 6548 :-)

we had 2-3 times so far the problem, that the ground connection on the frame below the water bottle
was bad and caused low voltage readings and strange behaviour of the tach when turning the car/key off.

BTW - 6577 is here in Germany :-)

Elvis

[kings1527]

...say hello from sister 6548 :-)

we had 2-3 times so far the problem, that the ground connection on the frame below the water bottle
was bad and caused low voltage readings and strange behaviour of the tach when turning the car/key off.

BTW - 6577 is here in Germany :-)

Elvis

Haha! This is interesting! Since we're part of the same build "family", I'm not surprised we're having the same issues! I've had the tach problem you just described, as well.

And you're talking about the ground on the passenger side engine compartment that goes from the bulkhead connectors to the frame? I'll have to double check that connection. I know I did mess with it while I was painting the engine compartment about a month ago. I'm definitely going to go with Hervey's double ground wire and hopefully that helps with the problem(s). The more I read, the more I find out that it's far less likely a bad volt meter/gauge.

6575 and 6577 together again! Online! Haha!

Alex
6575

[cybercusp]

Well, we took apart the binnacle this weekend and cleaned all of the contacts. Initially the volt gauge worked well but after a few minutes dropped out again. It works intermittently, so after talking to Dave at DMCMW I'm planning on doing the ground service next spring. Thank you again Dave for your help!