Strange Electrical problem

[Bedwards]

I am having a similar issue with my '11 Z1. I have constant power, but all my gauges will go to 0.00. KoolAid suggested I check the 12 pin connector at the dash and I thought I had found one that wasn't clipped together fully. It seemed to correct the issue. Now the problem is back. I've inspected the medallion plug and it looks good. How would you test to see if medallion is bad? Does the same 12 pin connector that carries power to the dash also carry the communication wires? One is labeled "O" with magic marker (this one cuts power to the dash) another is labeled "B". There are multiple other connectors as well. Both of the 12 pins I found looked good. Where is the 20 pin at the motor found?

[IDBoating]

A couple of tips while everyone is checking connectors:

* CAN requires a good ground reference too. Strictly speaking a differential twisted pair shouldn't require ground, but in the real world CAN transceivers struggle without a good ground reference. So check those grounds while you're at it.

* One way a contact in those 12-20+ connector housings can become intermittent is by backing out slightly from the housing. A quick glance won't always reveal this. The contacts in those white Molex connectors are held in by a pair of "wings" that can get squished back if the male and female housings are forced together once when all of the contacts aren't aligned properly. Voila - you have the opportunity for an intermittent connection! Be sure to press each wire individually from the wire end inwards, toward the housing, and then push-pull to make certain there is little to no play. If there is play, back the contact out and rebend the "wings" so they snap firmly when you reinsert the contact.

Hope this helps!

[Bedwards]

Thanks ID. When I said "looked good" I meant I pushed\pulled on them and all seem good. Since then I've checked continuity between all the gauge wire harnesses and medallion. All test continuous as they should from the schematic Justin at Tige sent me. I am reading 7v+\- at the red wire with white stripe at the gauge and 6v at the yellow wire at the gauge. Is this correct? I also checked continuity between the 8 pin and 20 pin connectors at the motor to the computer. Only one wire on each had continuity. I have the 343 PCM. Wire on the 8 pin hits the #16 socket on the medallion and wire on the 20 pin (#16 socket) hits #2 on the medallion. Sorry if i hijacked the thread, but sounds like the OP was having similar issues. Any help would be greatly appreciated!

[IDBoating]

I don't know the wiring for those connectors - I had to work out which were the CAN signals "way back when" and soldered in my own separate connector at that time. If you've checked all of them and they ring out fine, then you should be good in that department.