Ammeter AGAIN....??
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
Ammeter AGAIN....??
OK guys, I have used the search function...
1972 Coupe, small block, auto...
I have read all about "fusible links"...
I know some say replace it with a 80's GM voltmeter...
I know there is GREAT debate as to how much juice the ammeter can handle...
I know there are lengthy discussions about "shunts"...
I read that it is really a "millivolt" meter...
After ALL THAT (and more)... CAN SOMEBODY PLEASE TELL ME EXACTLY (and simply) HOW I CAN DETERMINE IF MY AMMETER IS GOOD OR BAD???? And... HOW TO TROUBLESHOOT???
Symptoms...DEAD
Observations...
-I light up my test light on both terminals of the meter
-I light up my test light on both sides of the fusible links, one at the horn relay, and the other at the wiper motor
-All other gauges and lights function normally, so I know the center cluster gauge has a good ground
NOTE...I have TWO gauges, and BOTH show the same symptoms, so my gut says it probably is a car wiring issue...although I guess it's possible that both gauges may be bad...
Is there anything else I can provide to help troubleshoot?? I DON'T have a multimeter..
Thanks!!!!
1972 Coupe, small block, auto...
I have read all about "fusible links"...
I know some say replace it with a 80's GM voltmeter...
I know there is GREAT debate as to how much juice the ammeter can handle...
I know there are lengthy discussions about "shunts"...
I read that it is really a "millivolt" meter...
After ALL THAT (and more)... CAN SOMEBODY PLEASE TELL ME EXACTLY (and simply) HOW I CAN DETERMINE IF MY AMMETER IS GOOD OR BAD???? And... HOW TO TROUBLESHOOT???
Symptoms...DEAD
Observations...
-I light up my test light on both terminals of the meter
-I light up my test light on both sides of the fusible links, one at the horn relay, and the other at the wiper motor
-All other gauges and lights function normally, so I know the center cluster gauge has a good ground
NOTE...I have TWO gauges, and BOTH show the same symptoms, so my gut says it probably is a car wiring issue...although I guess it's possible that both gauges may be bad...
Is there anything else I can provide to help troubleshoot?? I DON'T have a multimeter..
Thanks!!!!
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
You realy need a VOM.
But, you can test the meter itself with a flashlight battery and a light bulb and a couple alligator clips or jumper wires
Connect one of the battery to one terminal on the meter the other side through a brake light bulb and the other side of the bulb to the other terminal on the meter, JUST TOUCH IT and watch for the needle to move.
The bulb will not "Draw to much power" it is there to limit the current going through the meter
This is much easier with a multimeter, even a cheap one
But, you can test the meter itself with a flashlight battery and a light bulb and a couple alligator clips or jumper wires
Connect one of the battery to one terminal on the meter the other side through a brake light bulb and the other side of the bulb to the other terminal on the meter, JUST TOUCH IT and watch for the needle to move.
The bulb will not "Draw to much power" it is there to limit the current going through the meter
This is much easier with a multimeter, even a cheap one
OK guys, I have used the search function...
1972 Coupe, small block, auto...
I have read all about "fusible links"...
I know some say replace it with a 80's GM voltmeter...
I know there is GREAT debate as to how much juice the ammeter can handle...
I know there are lengthy discussions about "shunts"...
I read that it is really a "millivolt" meter...
After ALL THAT (and more)... CAN SOMEBODY PLEASE TELL ME EXACTLY (and simply) HOW I CAN DETERMINE IF MY AMMETER IS GOOD OR BAD???? And... HOW TO TROUBLESHOOT???
Symptoms...DEAD
Observations...
-I light up my test light on both terminals of the meter This is correct
-I light up my test light on both sides of the fusible links, one at the horn relay, and the other at the wiper motor Also Correct
-All other gauges and lights function normally, so I know the center cluster gauge has a good ground Good
NOTE...I have TWO gauges, and BOTH show the same symptoms, so my gut says it probably is a car wiring issue...although I guess it's possible that both gauges may be bad...
Is there anything else I can provide to help troubleshoot?? I DON'T have a multimeter..
Thanks!!!!
1972 Coupe, small block, auto...
I have read all about "fusible links"...
I know some say replace it with a 80's GM voltmeter...
I know there is GREAT debate as to how much juice the ammeter can handle...
I know there are lengthy discussions about "shunts"...
I read that it is really a "millivolt" meter...
After ALL THAT (and more)... CAN SOMEBODY PLEASE TELL ME EXACTLY (and simply) HOW I CAN DETERMINE IF MY AMMETER IS GOOD OR BAD???? And... HOW TO TROUBLESHOOT???
Symptoms...DEAD
Observations...
-I light up my test light on both terminals of the meter This is correct
-I light up my test light on both sides of the fusible links, one at the horn relay, and the other at the wiper motor Also Correct
-All other gauges and lights function normally, so I know the center cluster gauge has a good ground Good
NOTE...I have TWO gauges, and BOTH show the same symptoms, so my gut says it probably is a car wiring issue...although I guess it's possible that both gauges may be bad...
Is there anything else I can provide to help troubleshoot?? I DON'T have a multimeter..
Thanks!!!!
Race Director
Joined: May 2006
Posts: 16,528
Likes: 52
From: Dayton, Ohio
To use a test light you need to open the circuit by removing 1 of the wires from the meter.
(both wires going to the meter come from hot sources , so naturally both terminals will be hot even if the meter is open)
(both wires going to the meter come from hot sources , so naturally both terminals will be hot even if the meter is open)
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
You realy need a VOM.
But, you can test the meter itself with a flashlight battery and a light bulb and a couple alligator clips or jumper wires
Connect one of the battery to one terminal on the meter the other side through a brake light bulb and the other side of the bulb to the other terminal on the meter, JUST TOUCH IT and watch for the needle to move.
The bulb will not "Draw to much power" it is there to limit the current going through the meter
This is much easier with a multimeter, even a cheap one
But, you can test the meter itself with a flashlight battery and a light bulb and a couple alligator clips or jumper wires
Connect one of the battery to one terminal on the meter the other side through a brake light bulb and the other side of the bulb to the other terminal on the meter, JUST TOUCH IT and watch for the needle to move.
The bulb will not "Draw to much power" it is there to limit the current going through the meter
This is much easier with a multimeter, even a cheap one
Thanks Roger..
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 27
From: Florida
Plan on getting internet down here.
Yes,once I get settled in permanently,hopefully I'll be back down there by Sept of this year. 
