Another electrical issue

[thistle3585]

I have a '78 CJ5 that I am having problems with the turn signal. The right turn signal works but the left turn signal and hazards blow the turn signal fuse when I turn them on. They'll flash the dash and courtesy lights then blow the fuse. Obviously, I have a short somewhere. They worked when I bought them but I must have knocked something loose while cleaning up some of the wiring.
I know very little about automobile wiring and the wiring diagram really doesn't help me out much either. I figured the best way to isolate the problem was to start disconnecting stuff until it quits blowing a fuse and I could locate the problem. So far, I have deduced that it isn't the rear lights or harness nor is it the bulbs in the speedo. I doubt its the turn signal switch or hazard switch. All that aside, is there some way the experts track down a short in the system? What am I missing? Any suggestions?

 

[BusaDave9]

I just repaired a short in my lights. In my case it was a short in the high beams. It turned out that the insulation wore through and 12 volts shorted to the grill when the high beams were on. I was amazed how brittle the insulation was up front. Elsewhere my wires seem to be fine. I also have a '79 Jeep CJ.
It sounds like you know how to trace the short down.

I figured the best way to isolate the problem was to start disconnecting stuff until it quits blowing a fuse

Unfortunately it's hard to disconnect much. It is very unlikely that a bulb itself will blow the fuse so removing bulbs wont help. If you can disconnect connectors to the lights that will help but most of these lights don't have connectors. I think the only connector you can disconnect is one going to the tail lights. The turn signal switch is too much of a pain to disconnect.
Shorts can be a PITA to track down. Before spending too much time I would visually check the wires. Especially the green and white wire under the hood to the left turn signals. If my wiring diagram is correct the left turn signal comes out the firewall on the drivers side, pin T of the big connector. From there it goes to the left turn signal and splits off to the marker light on the left front fender.
Good luck.

 

[thistle3585]

Thanks. Are the side lights supposed to blink with the turn signals?

 

[BusaDave9]

Thanks. Are the side lights supposed to blink with the turn signals?

Yes, they could be the cause of the short.

 

[thistle3585]

Good news, I found the problem. It was the large flasher fuse/relay for the hazard lights. It had been put in wrong and was shorting out.

 

[Jdtm]

do you guys know where i could find a diagram of the fuse box? the letters on mine are worn out and i dont know which is which

 

[dzltech]

check your wiring to your left turn signals,front and rear,trace the wires down the tub and to the rear tail light then up to the left front turn signal. If your fusebox has plastic blade fuses,get a circuit breaker from Autozone and use that to make it easy to track a short. Circuit breaker will pop and you can reset it or find one that resets itself. Then trace your wires down,feel for a warm harness and that will be it. You can also buy a short chaser from Autozone or whoever that will make it easier on the diagnosis