Weird 1971 Challenger turn signal issues FIXED!

[KillerBee]

So I'm driving down the freeway today heading to the Mid Ohio Mopars show and all is good.

I hit a dip/bump in the road that jostled the car pretty good...the radio goes dead.
I checked everything else out and everything seems to be working so I figure it blew a radio fuse and kept driving.

About 10 minutes later the radio turns back on and at the same time the right turn signal light on the dash comes on and stays on.

I pull over and find the right front turn signal is stuck on(in the bright mode) on the front of the car, even when the ignition is turned off and the key is removed.
I thought at first it might be a bad bulb but it looks good.

I'm confused as the turn signal bulb that is stuck on should go off when the ignition is turned off.


So in checking everything out currently:

-The right front turn signal light is constantly on(both on the dash and at the front of the car) even when the ignition is turned off and the key is removed.
-Left turn signal works as it should but also works when the key is removed.
-Hazards are not working

Everything else seems to work properly.

I have little electrical wiring experience but I'm thinking possibly the ignition switch is bad?

Any suggestions as to where to begin checking?

Thanks.
 

[1 Wild R/T]

Sounds odd but I'm thinking turn signal switch......   If you have access to a switch just plug it in, you don't need to change it, just plug in a new/different part...

[KillerBee]

That might be possible, I have a complete manual column I just removed from the wife's Challenger to swap in power steering.

I hate to disassemble the column just to remove the turn signal switch and wiring to test, maybe just set the other column in the car and plug in the connector.

First I'm going to check all the current wiring and fuses and pull the steering wheel to inspect the current turn signal switch.

[TelisSE440]

The first thing that comes to mind is the turn signal switch since the Hazzards are not working. As you said  check the fuses, and wiring first, if you don't know which fuse gives current to the turn signal, remove them all one by one, until you see the signal going off, to find the culprit. But also check in every fuse case that you have current on both fuse clips. My hazard didn't work once, and it turned out to be corroded fuse clips where current could't flow. One last thing, I had the exact same problem (if it could help) with the dash light and front right turn signal light being on, the problem was (WHAT ELSE ON MOPARS?) a ground issue. The right front signal switch has an aluminum case that attaches to the front valance frame and all those works as a ground, if not grounded properly it creates feedback so you see these specific lights turn on. Anyway my guess is that the t/s switch is the half problem because the only way for the turn signals to work without key is if they're getting current from the hazards, you don't happen to have you hazard switch stuck open when checking the turn signals do you? Anyway, good luck...

[KillerBee]

Yes getting a good ground on those aluminum turn signal housings can be a pain.

I'm thinking if I disconnect the wiring plug to the turn signal near that aluminum housing if the dash light goes out I might be on the right track.

I'm starting to lean strongly towards the turn signal switch.
It makes sense that if the constantly powered hazard switch is shorted it would send power to the turn signals even with the key removed.

[72rtchallenger]

I wouldn't rule out the ground issue as pointed out , when I was installing my tail light harness after paint , some of the lights just came on when plugged up and not turned on as electricity searches for ground and as soon as I grounded the light housing the lights went off and worked with switch

[KillerBee]

Would the bad ground cause both turn signals to have power even when the key is turned off and removed from the ignition?

[72rtchallenger]

it could but not necessarily

[1 Wild R/T]

Would the bad ground cause both turn signals to have power even when the key is turned off and removed from the ignition?

No... Power is coming from somewhere... And since the turn signal switch has full time power to operate the hazard flashers plus it's part of the turn signal circuit it's the most likely source of your issue... You've got a spare column, the first thing I'd do is plug it in, you'll either have your issue pinpointed or have eliminated it as the problem... My bet is you'll have pinpointed the issue... 

[KillerBee]

God news it's fixed!

Well guys stuff like this really bugs me so I dug into it as early as I could.

In doing a visual all the fuses and wiring looked good.

All the screws that ground the aluminum turn signal housing looked great.

I disconnected the turn signal switch plug at the bottom of the column and the front turn signal light and dash light still stayed on with the battery hooked up

The bulkhead connectors at the firewall seemed a little loose so I pulled them all, inspected, cleaned  and reinstalled them with electrical grease.

Still no change.

I decided to check out the inside of the bulkhead connectors under the fuse panel.

I'm not sure of it's exact name but I discovered the larger gauge black wire located in the bulkhead connector closest to the master cylinder had over the years rubbed against a number of other wires and the black wire was exposed and grounding.

None of the wires appeared burnt or melted but some were sure twisted and rubbing around each other.

So I separated and inspected all the wires, covered the exposed parts of the black wire with electrical tape and made sure all the wires were playing nice with each other and reassembled everything.

Well that seemed to fix everything perfectly and it's back to normal.
That bump I hit on the freeway must have been enough to really ground that black wire to something.



I grabbed a fire extinguisher and took it for an hour ride and everything worked perfectly.

I assume that black wire is a ground and I will be keeping an close eye on it.

Thanks for all the advise it sure feels good to get things like this sorted.

[1 Wild R/T]

Cool...  That black lead is not ground, it's power & it supplies power to everything, it's pretty heavily loaded electrically...   It feeds the back of the Ammeter & from there it feeds practically every electrical load on the car....  You might want to consider cutting away the harness tape & looking further just to be safe.... 

[KillerBee]

Cool...  That black lead is not ground, it's power & it supplies power to everything, it's pretty heavily loaded electrically...   It feeds the back of the Ammeter & from there it feeds practically every electrical load on the car....  You might want to consider cutting away the harness tape & looking further just to be safe....

I did cut the harness tape to check the black wire, everything looked good.

The factory ammeter was bypassed when I bought the car.

What is the larger gauge red wire that is located in the center bulkhead connector, I believe it was at the bottom, I thought that was the main power feed.

[1 Wild R/T]

One lead comes in from the battery, the other to the alternator... Both are high current 12v leads...   FWIW the link below is the full schematic with all  the options...

http://www.mymopar.com/downloads/1970/70_Dart_Challenger_Wiring_Full.pdf

[TelisSE440]

Congratulations!!  Good to have solved the problem. The large red wire goes from the starter relay to the bulkhead connector and to the ammeter where through it, gets connected with the black wire you described and from there, to the alternator stud.

[KillerBee]

One lead comes in from the battery, the other to the alternator... Both are high current 12v leads...   FWIW the link below is the full schematic with all  the options...

http://www.mymopar.com/downloads/1970/70_Dart_Challenger_Wiring_Full.pdf

Thanks for the diagram.