M20 Gauge Sensor not working

[e30austin]

1989 325is with stock M20B25. Gauge worked perfectly for a while, then it was dancing around (like it had a loose ground on the back of the cluster,) and stopped completely altogether and now sits right below the cold (as if it weren't even turning on.)

I installed a new temp sensor and a known working gauge and it still isn't doing anything. What is the resistance supposed to be on the plug coming from the harness? It almost screams a grounding issue, but I'm not sure.

Thanks.

[jlevie]

The ground for the sensor is the engine block. And the ground for the block is the ground strap between the engine and chassis on the lower left front of the engine.

[Gregs///M]

Tighten the 7mm nut behind the gauge. Double check the engine ground as Levie recommended. If your Si board has the original batteries, they are dead and need to be replaced.

[e30austin]

7mm nut was tight. I'll check the engine ground strap and then replace the SI board batteries, if that's a no-go.

Thanks!

[Lingurade]

i need a main ground cable.. ill order one