Pre OBD...

[Tee]

A friend of mine has a 91 Olds 98, that's having a weird problem. It has the full digital/LCD dash; the problem is that after driving for a few minutes, it shows the battery voltage to be out of spec, something like 16v or something like that. I put my meter in parallel with the batter at idle and the voltage is actually ~14v; so it's fine. My question is, does this vehicle have a sub controller for the dash or does the ECU control everything? Lastly is there anyway to put this vehicle into diagnostics like you can with Cadillacs? Thanks, ya'll are the best!
Regards,
Tee

[Tee]

Update...

I got ahold of the schematic the other day and I found that there's a seperate wire that runs from the back of the alternator to the PCM and then to the cluster, I'm going to follow the wire with my meter and see what I get. The problem may be PCM related after all.
Regards,
Tee

[SappySE107]

Good to know. I have no idea what that setup is like or why it would say there is an error if you don't show that voltage at the battery.