car: 1985 RX7 12a

problem: fuse keeps blowing. the one that runs the gauges tail lights, deck, and head light motors.

we think maybe a motor is jammed or something causing an overdraw. even with a 20 amp fuse into what uses a 10 amp slot its blowing.

any ideas fellas? right now its just trial and error, more of th latter.

 

Does it blow the second you put it in? or when you try to use a specific accessory?

 

instantly.

my buddy has been working throuh it since its in his shop.

 

Start by unplugging all the things you can that are powered by that circuit, and then plug them back in one at a time until it pops (use a 10-amp fuse or lower; no sense in burning up wiring).

If it still blows when you have all the loads unplugged, its a short somewhwere in the harness.

You can check for a jammed headlight motor by using the manual override, too.

 

excellent, ill try that.

 

Exactly which fuse is blowing? If you are sitting in the driver's seat, the 4th fuse back from the front of the car on the left side is a 10 amp fuse. This fuse protects the circuit which supplies power to the dash lights, parking lights, side marker lights, tail lights, glove and storage box lights, overdrive switch and a few other items. Headlight motors and lights are on another circuit. Is this the fuse? If so, check the auto transmission select light wires. These wires are in the center console under the shift boot slightly to the left of the shift lever. There is a black wire and a red/blue wire. The black wire has a male plug and the red/blue wire has a female plug. In a manual transmission car they should not be plugged into anything. If they are plugged into each other, the circuit discussed above will be shorted directly to ground. Usually the dimmer control is burned out when this happens as well as the fuse blowing.

 

If the fuse blows the second you put it in then its a problem with the power side of the circuit i.e. unwanted grounding somewhere before one of the accesories applied within that circuit. First thing is to find all the circuits integrated into that and then figure out which have the highest traffic and trace the circuit to see if one of the wires is disconnected and grounding somewhere or if the switch itself its stuck.