dogbiscuit
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Hi, is there a process to troubleshoot a non-working factory tach?
Trouble shooting tach
- Thread starter dogbiscuit
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69 Cougar XR7 460/C6
Not really. If you unplug the tach and use an ohm meter across the two leads you should get resistance. If no resistance the board is bad.
If you have resistance of 1 ohm and the car will start and run but the tach doesn't move, yup, you guessed it - the board is bad.
If the needle doesn't move freely (float) the movement is bad.
If you have resistance of 1 ohm and the car will start and run but the tach doesn't move, yup, you guessed it - the board is bad.
If the needle doesn't move freely (float) the movement is bad.
dogbiscuit
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- 1971 Mach1 429SCJ Ram Air Drag Pak
Fixed my tach issue. I am using a Pertronix 2 ignition and had the ignition module wired to the + side of the coil, along with the stock tach feed wire. I removed the P2 from the coil and wired the ignitor direct. Tach now works!
You're a lucky guy. In most cases, when the original tach gets full 12V, it's toast.
Cheers Frank
Cheers Frank
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