PipeJones

iTrader: (1)

I've replaced all the gauges in the dash with autometer, fuel, temp, oil pressure, tach, and speedo. They all work fine but when I turn the lights on to illuminate the back bulbs, the fuel and oil pressure peg out, and the speedo odometer looses power. I experimented with my own hot 12 volt to the lights and they come on and don't peg out, odometer stays on, but the fuel slowly rises to full instead of staying at a half tank. In the process my oil pressure is stuck pegged way past full. It's weird, it all seems to work fine when dash is out on the bench and I apply power gauges respond normal. When in the car it all goes to ****. I've got the multimeter out and checked my switched power for main, and switch for lights. all show 12 volts when tested. I'm stumped I know it's a mess of a lot of information, but if anyone can decipher out what's going on and knows a tip to start troubleshooting, I'd owe you one.

John_D.

iTrader: (2)

Weird. At first I thought if you had a bad ground the power for the light might be backfeeding through the gauge inputs, but all that should be isolated from each other inside the gauge. Might be worth double-checking the ground for the lights anyway.