NEED HELP! Problems with new parts from DMCH

[jagee]

I got my new volt/temp gauge from DMCH today. I went to test it before I put it in and it's a good thing I did. It didn't work! My old volt gauge worked but read about 2 volts lower than it was supposed to (when the alternator was putting out 14 volts, the gauge only showed 12) so I compared them and found that the resistor on the back of the new gauge was bad. It was reading about 5 Mega ohms and the old one was reading 126 ohms.

Does anyone know how much resistance it's supposed to have? I'd hate to put the old resistor on it and it still read low.

Thanks

[dmc6960]

I know it doesn't help with the new part (you need to call them to deal with that), but if the old one was reading a constant 2v too low, it likely could have been a poor connection at the back of the cluster, or a corroded fuse #5. Odds are it was reading generally right, only it's input voltage was wrong. If it turns out that is not the case, you attach the PROPER leads to the volt gauge with a known input, then pull the needle off and reseat it at the proper location.

[Bitsyncmaster]

I wonder if those resistors are the same on all units or are a way to calibrate each gauge. I would think they could make the gauge accurate without "trimming" each unit. I would just wire it up to your test voltage and verify it reads the same as your multimeter. If not, put your old resistor on it.

You can also try to make the ground modification I did with the inertia switch ground. When I did that change my volt gauge indicated higher.

[Canon20DFan]

Immediately send it back to DMC! If you modify it or try to fix it, they can't take it back.