93 Riviera, dash electrical issues, what to do next

[kinnsk]

We have a 93 Riviera that's been in the shop for about a month now with electrical issues.  Started with all lights on the all electrical dash coming on and flickering.  Three shops later they sent the cluster from behind the dash to a place on the east coast (we're in San Diego) to rebuild it.  Came back, still showing intermittent error codes but only when installed, so better but not 100%.  They sent it back to the east coast, got it back and it's still showing intermittent error codes.  I'm obviously a novice to all of this, but I think the shop we're with is doing a fare job of trying to debug, I'm just wondering what to try next...  Any advice appreciated, the car is in good shape and has sentimental value but needs to pass smog for it's next registration and I'm at a loss what to do next.  I'm worried we're on the path to donate as non-operational, which would be just so sad on all fronts.  As is, since the car is having issues beyond us, even if we get it working we will likely need to sell to someone who can better take care of and appreciate it.  Thanks in advance

[RivNut]

Re-post this concern in the Reatta forum.  Lots of Reatta owners and the Riviera and the Reatta are basically the same car.

[Byondxtrme]

Possible body control module????

[kinnsk]

Thank you both.  The shop is looking into the other control modules and said they are currently suspecting the body control module, but are trying to confirm before sending it out so thank you for that tip.  I'll also repost in the Reatta forum as advised.  Thanks again.

[RivNut]

1 hour ago, kinnsk said:

Thank you both.  The shop is looking into the other control modules and said they are currently suspecting the body control module, but are trying to confirm before sending it out so thank you for that tip.  I'll also repost in the Reatta forum as advised.  Thanks again.

Those guys are wizards when it come to figuring out those electrical gremlins that play havoc with your instrument cluster.  

[Byondxtrme]

May sound crazy but I have had a friends Saturn do the same but was just the alternator overcharging, sending 18 volts through the system freaking everything out. Easy check for them.