hey I was wondering if anyone could help me out. I have a 97 gmc jimmy and I'm trying to get my DIS to fully function again. when I bought this thing it worked except for the temp, now it doesn't work at all. it let's me scroll through all of the selections but from the compass to the fuel range ext.. is all hash marks and the compass will not calibrate. is there a dead fuse somewhere, a broken wire or is the unit just dead in the water

 

Sounds like it is not getting any inputs to the the DIS from the various sensors. That they are all not working could mean it is likely a common electrical connector that could be bad.

 

The two power fuses for the DIC are: Ctsy Fuse 2, 20A and Radio fuse 11, 20A both in the I/P fuse panel. The data for that display is transmitted on a single wire multiplexed data line so there is no easy way for the shade tree mechanic to diagnose the data input to the module. To Christine's point there may be a connector issue. There are the connectors on the back of the module and the upstream data line connector is located below the left side of the I/P fuse panel. Any power issues affecting the data lines would be causing all kinds of problems throughout the truck. Beyond that, swapping a known good module is about the only simple way to rule out the display if power is confirmed at the module.

George

 

so i tried swaping out fuses, that didnt seem to work, pulled apart the entire overhead and checked all my connections in the DIC. tore the DIC apart and tested all the leads on the board. its all good in there. do you happen to have a pin out of the upstream connector?

 

What year is your Blazer? I can try to look in my 99 Service manual for the schematics for you.

 

Semi related, Mine doesnt work at all, wont even turn on so pinouts would be useful for a 1999, his is a 1997 per the OP post.

 

George

 

Looks like George has the right schematics.

Good Luck!