1990 suburban Gage/idle fuse circuit shorted

[gmbellew]

driving today and all of a sudden had no gauges. ECM was still reporting all the right data - coolant, vss, volts (although volts were lower than normal), etc. also noticed that when I turn the lights on, the buzzer buzzes....bc it thinks the ignition is not on.

found the gage/idle fuse blown, and it pops as soon as I turn key to ON.

looking at the wiring diagram, it looks like this circuit only feeds the cluster, gauges, and convenience center that controls the buzzers, etc.

am I missing something on this circuit, and what's the best way to try and figure it out?

truck runs and drives fine, only other symptom is the voltage is about 12.3 vs the normal 13v+ at the battery. could this be an alternator issue or maybe ign switch?

 

[gmbellew]

update - that fuse sends power to the TCC brake switch also. the purple wire from the brake switch that runs down to the TCC solenoid at the transmission was worn threw at a bracket holding the loom right by the connector. I moved it off the bracket and it didn't blow the fuse when i turned the key to ON. I'll wrap it up and reloom it in the AM. hope this helps somebody else in the future, and I'll update again if this wasn't the fix.