Hello, first of all let me introduce myself as I am new.

My names Kai Ive got a 69 122s with a b20b in it, I met some guys offa here at the vsccc car show last Sunday at stanley park and they recommend I check this place out so here I am.

Now my problem is that every time I engage my right hand signal light it blows the 25amp main fuse, you can actually see the fuse heating up to red hot and cooling down a few times before it blows, this only happens with the right hand signal, the left is fine. I have done all the usual stuff such as check the connections front and back at the lights for corrosion, shorts, or loose connections but those seem to be fine, I can follow the wires up until they enter the harness but then I'm lost (electrical isn't my strong suit). So I was just wondering if anyone had any suggestions or ideas to what it could be before I take it in and have to shell out some major cash to get it fixed.

Thanks, Kai

Hey, Kai

Craig's going to be the one to fine-tune my suggestions, but your problem is obviously that one of your right signal light wires is shorted to ground somewhere. This happened to Craig when something in his trunk pulled the wire out of his signal light and it shorted the circuit out. Actually shut off his car, too...

Anyway, if you've checked the visible wires leading to the front and rear right signal lights for abrasions & cracks, you're going to have to go a little further. I'm guessing the wires to the rear run through the rear side panel beside the back seat. There's probably lots of places for them to rub through along there. Towards your front, I'm guessing they run along the dash and out the right kick panel into the fender area.

That's basically it.

Matt (the shorter guy at the show who didn't say much)

Hi Kai,

Welcome to the forum. Matt's on the right track, as always and his memory is absolutely scary. I did have this exact problem (I'll revise that statement in a minute as it concerns electrical and I simply had the same presentation of symptoms) no that long ago. In my case the lead that goes to the turn signal bulb had popped off and grounded itself on the back of the light housing. This would pop the 25A fuse when the signal was on. I know you said that your wiring at the housing was fine - but if we trace the electrons, something is pulling way too much power.

First up would be a check to ensure that the insulator at the base of the bulb holder is intact. Take the lens off and pop out the bulb. Check to see if the brass contact has a phenolic (waffer fiber thingy) insulator between it and the side of the housing. If it is present, step 2 would be to see if you can heat things up by turning on the switch with the bulb out of the socket.

If none of that works (assuming you've got a multi meter or a test light), you can start tracing the wires. Turns are green IIRC. Check and clean with a stainless brush all the contacts on all your signal lights. Get rid of all the corrosion and find a cover plate for your fuse box (this will cause issues eventually).

Get some anti corrosion paste to help out your contacts. Now that that is cleared up, ensure your ground is good (the ground is the housing) - check to make sure you've got over 12V from the battery to the housing. Then start the trace from the back of the car to the turn signal. It is unlikely that anything went wrong inside the car.

Then start at the turn signal bucket at the front, trace it back (turn signal on and look for power) to the main harness. The connection is on the drivers side fender. Unplug the main harness from the front wiring loom. Have a look, any thing look wrong (are the wires hot)? Spray that connection with WD-40 and plug it in and disconnect several times, cleaning between connections.

There is no easy way to do this particular job.

Tracing electrical issues is just a matter of logic and time (and luck).
Craig

Thanks for the reply Craig. The volvos out right now getting the brake booster replaced but when I get it back I'll try out the things you have suggested. I do need a new cover for my fuse box, I go through those things so quick, I take it off, put it on the inner fender, and forget to put it back on and drive away haha, so if anyone has an extra then can throw my way it would be much appreciated.

So I got it figured out, turns out it was a combination of a bad warning light switch, and that when the guys who repainted my car put it back together they pinched the harness in the bolt holding on the radiator dam which happens to be right beside a clip that holds the harness real tight to the body so it was being very sneaky and not very noticeable.

sneaky!

i hate that about old wiring harnesses.