Circuit boards for gauges

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I’m being told that there are 2 circuit boards for my car. One for the tach , speedometer and fuel. And another for the three gauges in the center ( oil , charge and temperature) is that true? I was under the impression that it was only one board to control all gauges. Also I’ve seen a circuit board for the tach for sale in different catalogs but I’ve never seen one for the center gauges
 

Hemikiller

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The circuit board is only for the main cluster. There are two different types, one for tach, one for warning lights. The center gauges have a dedicated wiring harness.
 
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thank you that’s what I thought . My oil gauge stopped working and my temperature gauge goes to over heat level but sometimes they work properly (very rare). Do you think the problem could be the voltage regulator?
 
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Hi,
Remove the oil pressure sender and temperature connections and use attached resistors to check them. Note oil pressure has a stop in it at 3/4 the way to full pressure. Is Your fuel gauge is working? It should pretty much work the same with resistors below. You can measure voltage at temp sensor or oil pressure with them disconnected but you have to use a old fashion Voltmeter and it should read around 5 volts. The regulator behind instrument panel is a vibrator type. I hate this thing and have gutted it and installed a switchmode regulator from digikey inside of it. VX7805-1000 ( cui from digikey 102-4253-ND). You have to ground center of regulator to ground with a wire and wire terminal one to 12Volt connection and terminal 3 to 5 Volt out. This fixes regulator for ever! You can see post on 71-73 Mustang oil pressure gauge for more help.
Steve


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Joined
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Usa
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1973 Mach 1 completely stock ivy green with silver stripes.
Hi,
Remove the oil pressure sender and temperature connections and use attached resistors to check them. Note oil pressure has a stop in it at 3/4 the way to full pressure. Is Your fuel gauge is working? It should pretty much work the same with resistors below. You can measure voltage at temp sensor or oil pressure with them disconnected but you have to use a old fashion Voltmeter and it should read around 5 volts. The regulator behind instrument panel is a vibrator type. I hate this thing and have gutted it and installed a switchmode regulator from digikey inside of it. VX7805-1000 ( cui from digikey 102-4253-ND). You have to ground center of regulator to ground with a wire and wire terminal one to 12Volt connection and terminal 3 to 5 Volt out. This fixes regulator for ever! You can see post on 71-73 Mustang oil pressure gauge for more help.
Steve


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Thanks for the advice I will check it out
 
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