[buckhorn]

Do 1965 & 1966 mustang instrument cluster use same 5 volt pulse system? I have a 1965 mustang with a 1966 cluster & although I measure 5 volts, all guages are reading maximum. Anybody have a diagnosis plan ?

[The Greek]

Make sure that you have a good ground. The gauges are all the same except for the amp gauge, which you probably don't have. They are just labled differently. The gauge senders all indicate the same resistance about 70 Ohms for a zero or empty reading and 10 Ohms full or at maximum reading. Either there is a wiring problem or a bad ground. Are you sure that the gauge voltage regulator is properly wired? ---Chuck

[j_gallagher]

sounds like your instrument panel voltage regulator is bad and is letting a full 12 volts get to your guages. i am having the same problem in my 67. good luck finding a good one, i've been thru 3 already and am still looking for one that will last for more than a few minutes.

[deere1]

I replaced all my gauges with 12 volt, it doesn't look very original, but now I know what my car is doing.

[albert56]

You cad buy a solid state regulator at a radio shack store, LM7805 which is a 5V regulator, and the pin configuration should be on the back of the package, pin 1 is the input, 2 is ground and the tab, pin 3 is the output, you also have to install 2 .1mf capactors betwen the input and ground and the output and ground terminals..