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instrument cluster voltage regulator pulsating

7K views 5 replies 4 participants last post by  FEandGoingBroke 
#1 ·
So I tried to remove the cluster but it would not come out all the way.....I had enough space to test what I think is the voltage regulator..... the little square box bolted to the back of the speedometer.....on one side it reads 12 volts and on the other is pulses reading from sero to 11 volts.....never a constant reading....I'm sure that's bad......now my question is does the regulator affect the fuel gauge and temp gauge?.....none of them are working they move but stay near the lowest reading......could the regulator be the problem? I can't seem to find the coolant temp sensor on my engine so I have not tested that

Thanks
 
#2 ·
So I tried to remove the cluster but it would not come out all the way.....I had enough space to test what I think is the voltage regulator..... the little square box bolted to the back of the speedometer.....on one side it reads 12 volts and on the other is pulses reading from sero to 11 volts.....never a constant reading....I'm sure that's bad......now my question is does the regulator affect the fuel gauge and temp gauge?.....none of them are working they move but stay near the lowest reading......could the regulator be the problem? I can't seem to find the coolant temp sensor on my engine so I have not tested that

Thanks
The swinging voltage you are seeing leaving the instrument voltage reg is doing exactly as it should. The voltage never sits still. The fuel gauge and temp gauge get their voltage from that reg.

You can test the function of both gauges. Disconnect the sensor lead at each device and ground that wire. The gauge should peg the gauge. Leaving it disconnected the gauge should sit at the bottom. You can test the top scale reading by connecting a 10 ohm resistor to that lead and grounding it. Then connect a 70 ohm resistor and the gauge should read at the bottom of the scale. If they pass that test then the gauges and the IVR are working correctly. the problem has to be the sensors.

If in doubt on the IVR replace it with an electronic unit and you'll never have to replace it again. And with the electronic reg you won't see a swinging output voltage. It should read +5.1 v when set correctly.
R
 
#5 ·
thanks for the help everyone... i feel stupid i found the temp sensor.... that thing is tiny.....so i order a new one that one is bad....... so after cleaning the fuse holders and replacing some fuses i now have all the dash lights and heather working.... i'm so glad i wont freeze my but off in the mornings.... i still have to test the fuel sender but i'm almost sure is bad.....
 
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