[69Kat]

:1poke:
Does anyone know the spec's on the Constant Voltage Regulator (Instrument Panel Voltage Regulator) used on the 67-68 Cougar. I have a sneaking suspicion that mine is bad. Temp and Fuel gauges both peg out. I have already checked the wiring - Good, Sending unit-Good, and the Gauge- also good. So that leaves me to believe that the CVR must be bad, but I hate to spend the money just to part swap without knowing for sure. Mustangs Unlimited wants $22.00 for the part, but I can probably get it from the junk yard for $5.00 provided I can test it to make sure its good.

 

[Ray]

CVR

The CVR does not often go bad but if guages are reading incorrect that can be the problem. You sound like you have an incorrect ground as the needles are pinned. The guages work off variable resistance to ground. The CVR reduces line voltage from 12 to 7 approx. CVR affects Fuel Temp Oil pressure in xr7 and fuel and temp in Cougar. Its also possible the wire from rear of block to firewall is missing and that will cause needless to read wrong. You must be the only Cat w/o a spare dash cluster, I always thought a spare was a requirement,lol.Catzyalater

 

[69Kat]

CVR

Thanks Ray I checked my ground wire from the engine block to the firewall and it was loose. I have tightened it up and check everything again. Still no change. I read somewhere that I should have a 5 volt reading at the plug to the sending unit. does that sound right? I have already pulled the sending unit and the resistance runs between 10 and 70 ohms depending on where the float is. when I disconnect the lead wire from the sending unit the needle falls to empty. I haven't tested the temp sending unit, but the temp guage pegs out without the engine running.