2004 Pontiac Grand Get Wiring Diagram Gauges Dash

I think you need to check for applicable trouble codes, first. Some of the national brand autostores will check codes for free. Several of the sending units send signal to pcm, the pcm sends class2 data to the instrument panel cluster.

You can check fuses for the instrument cluster and you can check ground. The ground wire is black with white tracer. The fuses are in the diagram.

Thanks for your reply. I'm not trying to diagnosis a problem, trying to install new aftermarket gauges using existing feed wires.

Are the new gages/cluster compatible with the system?

How would I find that out?

If original instrument cluster connectors wont work with new cluster, you got problems, in my opinion. Did the new cluster come with wiring instructions? If not, I'm not sure how to help? I already explained how the original cluster works.

I have 5 wires from the existing harness for the gauges, I need to know which color wire goes to which gauge.The new gauges didn't come with wiring. The tach & speedometer doesn;t come with a sending union. I'm trying to hook into the existing harness, and need to know what color wires go to the tach & speedometer, all others come sending units.

Thanks!

This is for speedometer wiring. Voltage and ground.

The vehicle speed sensor sends signal to pcm. The Pcm sends class2 serial data signal to instrument for speedometer.

If you get away from factory set-up, I can't help you.

Thank you.