Electrical Gremlins (1 Viewer)

[bobrose]

Ok '86 fj60. The headlights stopped working, when I go to turn them on, ont of the relays under the dash starts buzzing, and the blower motor turns on (key is out) but I can't turn the blower up higher than the lowest setting, also the lighter doesn't work either, all these problems led me to believe it was a faulty ground, so of came the dash and I disconnected each of the ground one at a time to try and isolate the problem, no change. Could it be a bad relay that's causing all the trouble (the brown rectangular one buzzes, not blower control relay or wiper relay). Oh yeah, to make things better, after my tinkering the parking lights, which worked before, now only work if I turn them on before the engine, all this still sounds like a bad ground to me, so I'm baffled.... any ideas????? I got a feeling a shop would take my arms and legs as payment to fix this...


Bob

 

[godzilla]

Sounds to me like you have a short someplace. I had the same strange occurances on another truck I used to own. Although part of the problem was a ground, I had a new fender put on that vechile, and when they put the new fender on, someone forgot to hookup a ground wire, hench the gremlins.

 

[dogboy]

Take a multimeter, a wiring diagram, a ton of patience, a bottle of Advil, and your best cuss words and dive in..... Take it from the point of the problem, i.e. headlights not working and then work backwards logically until you find 1) the short 2) loose connection 3) corroded connection 4) loose ground 5) etc..... No offense intended here, but before you dive into the above, check the fuse box for a blown one and the connections to it.

My experience with this stuff to date is that it is very logical -- just work slowly and methodically, eliminating the variables as you work backwards from the immediately obvious. In your case, the buzzing relay sounds like a decent place to start: work upstream and downstream from that point after checking that relay out, working over all intersecting lines and anything that taps into that headlight circuit. The wiring diagram should identify the fixed locations around the vehicle where the main lines ground out to the chassis, if that helps.....

The crap/hack jobs that some PO's do to the rig before you get it can be amazing: you wouldn't believe the graveyard of abandoned wires, crummy splices, bare wires, etc..., I've found under my dash this week while relocating my stereo.

I feel your pain man,

-dogboy- '87 FJ60

 

[erfworm]

this sounds exactly like the problem I had with my 62, I mean exactly. After checking all relays, I took the dash apart and found a connecter, located off the main loom directly behind the gauges, was melted. This connector carries several ground wires and seems to act like a block to route them all into one main ground. After much discussion, I ended up just removing the connector, cutting out the bad sections of wire, lengthening them and soldering them all into one large ring connector. This "new" grounding block was then grounded to the steering column bolt and problem solved. However, it is important to find what caused this short in the first place, otherwise it may return. In my case, the previous owner had done some hack job on a ground wire which resulted in the ground being run through a badly burnt, corroded wire. As stated above get yourself a multimeter and try to locate the short. Another good thing but time consuming to dois to remove all the wrapping aruond the looms to inspect each wire for obvious damage. Hope some of this helps, like I said I had the same problem, but electrical s*** is weird so it could be something different. I'll keeping checking this post to see if you need any more clarification on what I did. Good luck,
Nick

 

[dd113]

All the other posts were dead on. I would do 2 things first. Disconnect headlight switch and dimmer knob. Look on a wireing diagram, make some jumpers and get the lights to work (or not) without using the switch.

 

[bobrose]

Thanks for the help guys, after pulling the dash out and peeling off all the black wire loom/tape I found the problem. A bus type connector that merged a bunch of ground wires into one had corroded/melted(some). I'm assuming that the corrosion caused the melting since I went over that circuit and couldn't find anything shorted or non-stock that would affect the ground. So I pulled the connector out, cleaned it up and put it all back in a way I could get to it easily in the future. Presto! And the man said let there be light, and it was good.

Bob

 

[hammerhead]

Corrosion causes resistance. Resistance causes heat. Heat causes resistance. Resistance causes...well...you get the picture. It's a vicious circle.

 

[erfworm]

Good to hear it Bob . Your problem seemed to be exactly what was going on with my 62 and I felt your pain. We're all glad your back in business