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Gauge questions

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Apparently my ammeter doesn't work. It never moves from a hair to the right of center. Lights and all on with the engine off - doesn't budge. How do I trouble shoot this? I've had the instrument cluster off and the wires are connected correctly back there.

Also, I don't believe my temp. gauge is working correctly, but the symptoms are very different. When I do a cold start, leaving the engine at idle, the gauge begins to move in about 30 seconds and after about a minute settles on about the 70% point, where it stays. That can't be right. What should I suspect there?


67 coupe, I6/200, and a C4
Randy (Learning as I go)
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Ammeter: remove your dash cluster after disconnecting the battery. Put a D-cell across the ammeter contacts, and see if it moves. If not, it is fried.

Temp gauge: Use Ford temp sending units. The reading can be controlled by adjusting the constant voltage regulator on the back of the dash cluster, but it will also affect the gas and oil pressure readings. That's strange that on a cold start it will read 70% within 1 minute. My best guess is that you have an aftermarket TSU, and it's not reading well. me check your shorts! My multimeter is just a-waiting! Formerly known as Midlife in the old VMF.
King of the Old Farts *struts*
...and to test your temp gauge, disconnect the wire at the sending unit and turn the ignition switch on. The needle should stay hard at the cold position. Ground the wire disconnected from the sending unit. With the ignition switch still on, the gauge should swing across the dial to the hot stop.

"Sometimes a man's life can depend on a mere scrap of information."-The man with no name
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