05 rxt gauges not working

[hypersniper2010]

have an 05 rxt supercharged ic that the gauges are not working. dealer said mpem and wire harness were corroded and ned replacement so I bought a used mpem and harness and installed it. ski will start and run no problem but there are still no gauges. there is a 4 wire harness going into the hood with black, red/white, black/white and red purple. the red purple has power all the time all the way to back of gauges (using a test light grounded to battery) when I probe black (as a ground in harness to gauges) and red/purple I get nothing key off or on.. is there any way to test the gauges them selves ?
thanks in advance

 

[mkov608]

I suspect your problem is internal to the information center (water inside). There is a 1A fuse on the MPEM for the information center. Check that first.

Don't get rid of that old MPEM; that probably wasn't the problem.

 

[hypersniper2010]

bought a brand new gauge cluster and still no gauges working.

 

[mkov608]

Have you checked continuity of all the wires between the MPEM and the cluster?