1987 Toyota Corolla Fuse Immediately Blows

LADYFSH

MEMBER
1987 TOYOTA COROLLA
4 CYL
FWD
AUTOMATIC
136,000 MILES

This is a Corolla FX16 with DOHC, which I purchased a few months ago. My mechanic is methodically going through and replacing/fixing all noticeable issues such as oil leaks and worn hoses. So far, it has gotten a new distributor, cap, plugs, wires, gasket seal, several hoses replaced and all motor/transmission mounts replaced, due to an incredibly rough idle and vibration (which reduced significantly, not did not resolve completely). Now the issue is electrical. The 7.5 amp fuse for the “gauges” blows as soon as you turn the key. This disables the gas, RPM and temperature gauges, as well as the heater/ac blower and rear defroster. Additionally, the back up lights do not work and yes, I’ve changed the bulbs just to make sure. I’ve seen a couple postings indicating the back up lights could be the culprit, that somehow, the gauge fuse and reverse lights are tied together. At first we thought the instrument cluster was dead, but replaced the gauge fuse right after I bought it and it worked for about a week and a half, then blew and has not worked since. Suggestions?

2 Replies

FLEXY5

MECHANIC
512 POSTS

The first thing that jumped out at me was the heater blower. Try unplugging the blower motor and see if that helps. Given that it is only a 7.5 fuse, I would think that the blower is run off a relay, but the relay fed by the fuse. If this doesn't work, start unplugging the different things fed by the fuse one at a time. You should eventually unplug something that does not cause the fuse to blow. Try this and post back. If you need further help, let us know.
Dave