Tach and Tach Lights
Thread Starter
6th Gear
Joined: Oct 2012
Posts: 6
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Tach and Tach Lights
Ok, I have to have a bad ground somewhere but don't get it, lets see if someone else has had this.
Here's what I've done, I put in a new flex circuit board for the speedo and tach, also replaced the tach board while I was in there
I zero'd out the tach and when I hit the key it powers up and goes to zero
When I'm driving it goes now where unless I'm really pushing her then it's only a few hundred Rpm's, the tach filter is bypassed, so that is issue 1
The second is all the Dash lights are working except those around the tach, Im looking over the wiring diagrams and there is only one ground
going to all the lights and the tach.
All fuses are good, new light switch with dimmer, new circuit board, tach board, it has to be something stupid that I'm missing any help would be great
Thanks in Advance
Here's what I've done, I put in a new flex circuit board for the speedo and tach, also replaced the tach board while I was in there
I zero'd out the tach and when I hit the key it powers up and goes to zero
When I'm driving it goes now where unless I'm really pushing her then it's only a few hundred Rpm's, the tach filter is bypassed, so that is issue 1
The second is all the Dash lights are working except those around the tach, Im looking over the wiring diagrams and there is only one ground
going to all the lights and the tach.
All fuses are good, new light switch with dimmer, new circuit board, tach board, it has to be something stupid that I'm missing any help would be great
Thanks in Advance
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
It sounds like you have something goofy going on with the signal wire. You could have a short somewhere else causing this issue too.
I would go to the schematic below.. and verify each wire. Test continuity from the clip for the tach to the distributor.
As for the bulbs.. did you test the bulbs before you re-installed them? The bulb and socket is famous for not making good contact.
Make sure you don't have voltage on either of the two grounds or the signal wire at any time.
Willcox
I would go to the schematic below.. and verify each wire. Test continuity from the clip for the tach to the distributor.
As for the bulbs.. did you test the bulbs before you re-installed them? The bulb and socket is famous for not making good contact.
Make sure you don't have voltage on either of the two grounds or the signal wire at any time.
Willcox
