tail/running lights stopped working.

[thebucketslider]

77 620kc. tail lights all the sudden stopped working, along with dash lights and side markers. front side markers are not hooked up, so i know why they dont work. the tail lights just stopped working recently. from what i can tell from wiring diagram, dash lights, and running lights are all the same circuit. i could not tell where the ground for that circuit is though. i looked under dash and no dice. will i have to remove the cluster to find it, or is it elsewhere in the harness? and it dosnt look like i have to remove the whole dash to get the cluster out or am i just seeing things? i tried unplugging and plugging in the rear chassis harness under the passenger side of the dash (small black plug) with no result. do the head light switch go out very often? sorry for the novel, any help is much appreciated!

 

thanks.

-mike.

[Eagle_Adam]

did you check the fuse? and the gauges come out separate from the dash

[thebucketslider]

yeah, all fuses where good, no corrosion on the fuse box either.

[Eagle_Adam]

did you check the back side of the fuse box? im assuming you've done all the basics just asking in case

[izzo]

they are on the same fuse. and part of the light switch also, try wiggling the light switch back and forth and see if they come on, even if they just flicker. (pull the light switch in and out, wiggling it around etc..)

 

I had an issue where a running light wire was rubbed raw to metal, touched the body and would fry the fuse... Found and fixed that, but they were slightly finicky working anyways because well used headlight switch.

[datzenmike]

77 620kc. tail lights all the sudden stopped working, along with dash lights and side markers. front side markers are not hooked up, so i know why they dont work. the tail lights just stopped working recently. from what i can tell from wiring diagram, dash lights, and running lights are all the same circuit. i could not tell where the ground for that circuit is though. i looked under dash and no dice. will i have to remove the cluster to find it, or is it elsewhere in the harness? and it dosnt look like i have to remove the whole dash to get the cluster out or am i just seeing things? i tried unplugging and plugging in the rear chassis harness under the passenger side of the dash (small black plug) with no result. do the head light switch go out very often? sorry for the novel, any help is much appreciated!

 

thanks.

-mike.

 

The ground for the tail lights is at the back on the frame. The chances of the tail light ground and the dash light ground failing at the same time is extremely unlikely.

 

Fuses should never be trusted by looks. Shove a quarter across the contacts of the tail lamp fuse to form a circuit around it. If the lights come on then the fuse is faulty or not making good contact with the holder.

 

As Tim Shady said the light switch may be at fault.

[Eagle_Adam]

Tim Shady

 

:rofl: :rofl: :rofl: :rofl: OMG tears - will the real tim shady please stand up

[thebucketslider]

ill check the back of the fuse block, hasnt burnt any fuses tho. when i first bought the truck the dash lights would trn off sometimes, but i ould hit the dash and they ould turn back on... thinking that has something to do with it.. there is a ground ire from the back of the cluster i think... looks like ill have to pull the hole thing out. the rest of the wiring harness is looking good though!

[izzo]

:rofl: :rofl: :rofl: :rofl: OMG tears - will the real tim shady please stand up

 

 

 

:rofl: :rofl:

 

If only everyone knew the story of why Adam is laughing is ass off right now. Oh the fun time I had in vegas...

[Eagle_Adam]

i wish i was there tim - far to funny to explain

[DISLEXICDIME]

look and see if one of the wires came un solder from the headlight switch

[Phixius]

Check continuity. Do you have a multi meter ? Ive traced a few electrical problems with a cheap meter... when i first got my 72 521 the running lights didnt work, after replacing the corroded fuse block i found that there was a corroded wire in the harness... and about a year later brake lights didnt work and ended up being a bad connection in a plug had to replace the end that inserts into the plug... a multimeter will help you eliminate possibilities and narrow it down...

[thebucketslider]

Yatzeeee!! Was the fuse.... After I got the cluster out, tested the switch, traced the harness, bought new switch, and tierlessly looking the harness scamatic ober and over, decided to do the quarter trick. Like magic. I just like the hard way.... Thank you fine gents for all the help!! Now I just need a clister bezzel thats not fooked.

[Eagle_Adam]

i know someone whos got one but he wants $60 for it :/ PM me if your interested

[datsundash]

mine also quit working recently. Upon inspection, my harness at the rear of the truck had been chewed by my 6 month old lab. Soldered and heat shrunk it all back together and presto!!! Lights again.