Lost my Tach

[guards73/2.0]

I fired up today and noticed that everything worked but the tach. I've recently pulled out the center console for service to the console wiring harness and disconnected all of the spade plugs that go over the tunnel and come out under the console by the heater switch, and I wondered if this might be my problem. Are any of these Tach wires? I'm also assuming that this is part of the reg. plate harness that goes to the coil.

[Dave at Pelican Parts]

The tach wire, AFAIK, goes straight back to the relay board. (And from there to the coil.)

I'd suggest checking for +12V on the red/white wire that goes to the tach--when the key is on, of course. Also make sure you have a good ground on the brown wire.

If those are both OK, then you either have some kind of problem with the black/purple wire that carries the tach signal, or the tach itself is kaput, or your ignition system is in poor shape.


--DD

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Pelican Parts 914 Tech Support

A few pics of my car: http://www.pelicanparts.com/gallery/Dave_Darling

[campbellcj]

My tach went dead a while back. It was intermittent (bouncy) for a while, then just died. The crimp connector at the coil had just worked slightly loose. It was still sitting on the male post, but the connection was bad.

Check the simplest things first!

Good luck,
Chris C.

[URY914]

The red/white wire is red with a thin white line on it. On my '73 the black/purple that Dave wrote about is all black. These are the three that plug in the back of the tach and go thru the tunnel.

[Dave at Pelican Parts]

Actually, I'd be surprised if that black wire of yours didn't have a purple stripe on it. (That is the color coding for all years.) However, the purple is fairly close to black in color (i.e., it's pretty dark), and it tends to fade to black as it gets old and dirty. It took me about 5 solid minutes of looking before I discovered the purple on my tach wire...

--DD

[murph914]

try tapping the glass while under way, they do get stuck sometimes too