Vot meter issue
Thread Starter
Burning Brakes
Joined: Jun 2009
Posts: 840
Likes: 4
From: Syracuse IN
Vot meter issue
My volt meter is now reading low, and now a red light appears in the back ground. But first some history, last week the car would not crank or start by pushing. I was 200 miles from home. I ended up finding a bad main ground cable by the frame. I jumped myself using a jumper cable from battery ground to engine. Car started great. I drove home no problems I did not shut off the entire time. Yesterday I replaced the bad ground cable, and now the volt meter is reading low. 9 volts and only registers when engine is running. If key is on nothing. The alternator is puting out 14 volts while running at the battery. The battery reads 12.4 while off. I do not beleive I have a charging problem, but I would like to get the volt meter registering correctly. Al
Thread Starter
Burning Brakes
Joined: Jun 2009
Posts: 840
Likes: 4
From: Syracuse IN
Maybe I need to clarify, the cars volt meter reads 9 volts and my DVM reads 14 while running and 12.4 while not running. The cars volt meter does not read at all with the ignition on but not running. And yes the battery's are good on the DVM. Thanks Al
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Thats an odd one. The voltmeter is pretty basic ,power and ground. Power comes from the 10 amp gauges fuse which powers most of your gauges so you would know if it was blown. Ground is shared by all the other gauges. I see you do have an 81 though and they can do strange things to the dash with the choke wiring , check your fuses.
Just guessing but maybe cluster printed circuit or a bad gauge , the printed circuit can also do some weird stuff.
Just guessing but maybe cluster printed circuit or a bad gauge , the printed circuit can also do some weird stuff.
Thread Starter
Burning Brakes
Joined: Jun 2009
Posts: 840
Likes: 4
From: Syracuse IN
I notice it has a printed board. Can I remove the gauge and test the board with a DVM? I am unsure about the red back ground light. All other gauges work fine. I was not sure if during the drive home without a proper ground could have damaged the volt meter. Al
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
If your meter reads ~14v at the alternator and across the battery terminals when it is running and it reads ~12v across the battery when not running then your charging system is good and you have a problem with the voltmeter in the dash.
You need to remove and fix the voltmeter in the dash or just run it as it is and occasionally check the voltage when running with your meter.
You need to remove and fix the voltmeter in the dash or just run it as it is and occasionally check the voltage when running with your meter.
