Was driving down the road and all of a sudden the tach jumped to 6,000 and stayed there and the voltmeter and oil pressure gauges went to 0, but the car was otherwise running fine. I started to head back home and noticed the engine bogging down under load. At this time the temp gauge also went straight up. I don't think it was actually overheating, just instrumentation issues due to this electrical problem. Upon inspection I found that fuse 5 was blown (labeled dash services). As far as I can tell from the wiring diagram if fuse 5 is blown the alternator won't run. I suspect the engine bogging was because I wasn't getting enough voltage for good spark. I replaced fuse 5 and it seemed to run fine, but then the fuse blew again just idling in my driveway after a few minutes. It might be worth noting the cooling fans cycled on and off just fine once I replaced the fuse, it appears the otterstat is tied into this circuit as well. I then replaced the fuse with my ammeter and it showed about 1.5A being pulled on fuse 5. This ran for a few minutes until suddenly the 10A fuse in my meter blew. So it seems like there's some kind of intermittent short in this circuit.
Does anyone know why fuse 5 would keep blowing? I checked the connections at the fuse block and traced the green wire to where it goes into the center tunnel and don't see any obvious issues. I can keep tracing it around but figured I'd ask here before I waste too much time.
Once last thing... I did notice that even after replacing the fuse the battery light would illuminate with the ignition in the "on" position (but engine not running) as normal but was pretty dim. The brake light right underneath was much brighter. I've owned this car for almost 19 years and I can't recall if that's how it's always been, just struck me as odd. Maybe that'll give someone a clue
Thanks!