Need help tracing ground problem
Thread Starter
Racer
Joined: Jan 2001
Posts: 251
Likes: 0
From: Toronto Ontario
Need help tracing ground problem
A while back I took apart the dash in order to replace the speedo needle, cable and a non working speaker on my '71. When I went to put the dash back in, my tach and speedo lights no longer worked. Looks like I messed up a ground wire somewhere as I can get the lights to work when I turn the light switch on and ground each of the lights housing to the chassis using a separate wire.
There is a ground on the left side above the kick panel with two black wires and they look to be OK. I also noticed that each of the tach and speedo have a ground wire that clip onto the back of the speedo and tach each. I tried to ground those wires separately, but nothin happened.
How do I trace or figure out which ground wire is the one that I messed up. Can anyone help me go through this systematically? I'm lost!!!!
Thanks.
There is a ground on the left side above the kick panel with two black wires and they look to be OK. I also noticed that each of the tach and speedo have a ground wire that clip onto the back of the speedo and tach each. I tried to ground those wires separately, but nothin happened.
How do I trace or figure out which ground wire is the one that I messed up. Can anyone help me go through this systematically? I'm lost!!!!
Thanks.
Melting Slicks
Joined: Mar 2002
Posts: 2,140
Likes: 7
From: Ohio
If you run a wire from a known ground ( I use the battery) and the bulb don't light you have a burnt out bulb or no power to the bulb. The headlight switch may have failed in the dimmer part of the switch as it is a coil and they fail often. If you twist the switch to full brightness it will click on and will usally work to light the dash lights when the dimmer is burned out.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
A while back I took apart the dash in order to replace the speedo needle, cable and a non working speaker on my '71. When I went to put the dash back in, my tach and speedo lights no longer worked. Looks like I messed up a ground wire somewhere as I can get the lights to work when I turn the light switch on and ground each of the lights housing to the chassis using a separate wire.
There is a ground on the left side above the kick panel with two black wires and they look to be OK. I also noticed that each of the tach and speedo have a ground wire that clip onto the back of the speedo and tach each. I tried to ground those wires separately, but nothin happened.
How do I trace or figure out which ground wire is the one that I messed up. Can anyone help me go through this systematically? I'm lost!!!!
Thanks.
There is a ground on the left side above the kick panel with two black wires and they look to be OK. I also noticed that each of the tach and speedo have a ground wire that clip onto the back of the speedo and tach each. I tried to ground those wires separately, but nothin happened.
How do I trace or figure out which ground wire is the one that I messed up. Can anyone help me go through this systematically? I'm lost!!!!
Thanks.
Jim
Thread Starter
Racer
Joined: Jan 2001
Posts: 251
Likes: 0
From: Toronto Ontario
Problem Found
As usual, it is something relatively minor that creates these type of problems. I did not connect the ground clips to the back of the speedo and tach housing. Without this, the circuit can not be completed. What threw me for a bit of a loop was that the parking brake light, which comes from the same group of wires, was able to turn on. What I didn't notice was that this light has two wires, obviously being able to operate on its own. The other wires are all one wire lights and hence need the ground wire to complete the circuit.
Anyway, off to the races. Thanks for everyones help.
Anyway, off to the races. Thanks for everyones help.
