Fueses Getting HOT!!

[texasz]

My tail light and brake light fuses keep blowing. I have put in the proper 20A fuses but they get really hot and blow immediately.

Any thoughts?

[civ104]

My tail light and brake light fuses keep blowing. I have put in the proper 20A fuses but they get really hot and blow immediately.

Any thoughts?

Check for corrosion around the light sockets. Also, if it has happened suddenly, get a multimeter and check for shorts to ground in the circuit.

[g72s20]

hey Allan,

Sounds like you got a short to ground (the car body metal). Simplified , the +12v that is supposed to be going to your rear light and brake globe filaments and then to ground/earth, is being diverted along the way to the car body,(shortening the path for the current, hence the term "short") or possibly to another wire that is grounded. To do this the insulation on the wires carrying the power to the lights has to be damaged/missing.

First up, can you use a multimeter? and are you reasonably comfortable with reading cct diagrams? If not, just check as much of the wiring harness as you can from the rear lights, working your way back toward the fusebox. Look for previous repairs to the harness, electrical tape that has been added, or bare wires from damaged/missing insulation.

If it is as you say both tail and brake light fuses, I'd be looking for something that could have recently squashed the harness, or look closely at any recent work where something may have been unscrewed or unbolted....replaced and inadvertantly crushed some wiring.

Sorry if this seems a bit all over the place, ideas occur as I type

I'm not familiar with the wiring layout of the Z's. Does it run under any interior floorcover that could have had something heavy dropped on it?

I'm sure you get the idea. I know it ain't easy, ya gotta look....but you also need to know what to look for. Let us know how you go, and I'm sure there will be plenty of other suggestions from others' experiences with Z electrics.

Good luck, I hope this helps.

Jim.

[Daniel]

The common location seems to be the rear light bulbs/ sockets. Sometimes one filament in a dual filament lamp( tail & brake) will fail/ burn into, and lay across the other good filament. In this instance you now have a SHORT, two or more positive/hot/ ungrounded conductors making contact. If one or more positive/hot/ungrounded conductors were to make contact with a negative/grounding or grounded conductor that would create a GROUND FAULT. The two are completely different. What happens with only one fuse installed? Do all lights work? Of course I dont mean with one fuse.I should have given the examples in a better order!

[seerex]

as written above check for breaks in the cover of the wire as well as at the socket , look for green buildup on the connections and inside the socket, another aspect i would consider would be checking the fuse box under the ashtray for a lose wire or maybe something that accidentally got in there, also check the back carefully for green build up or burn areas, clean the terminals with the fuses out of the box , only takes 2 minutes to remove it BUT REMOVE THE NEGITAVE SIDE OF THE BATTERY FIRST

[seerex]

I got the burn on my finger to prove its a good Ideal , clean the back of the fuse box and spray it with an inhibitor got my clean and spray inhibitor at home depot and works great , good luck

[EScanlon]

...REMOVE THE NEGITAVE SIDE OF THE BATTERY FIRST

Actually, all you need to make the whole system inert (in a 240) is to disconnect the fusible link going to the starter. That's the main power link for the car, and NOTHING will receive juice.

Check the schematic and you'll see.

Enrique

[seerex]

good point Enrique i just went a bit extreme after the finger issue