Left front turn signal

[SlinktRR]

70 roadrunner. Trying to track down my last lighting issue. Brake lights, emergency flashers all work. Rear turn signals work. Right front amber turn signal flashes. Side marker and front/rear running lights work with headlight switch. However the left front amber signal does not flash. My hood marker turn signals are disconnected and the FSM diagram shows these hooked to the same circuit as the front amber lamps. But the right amber flasher works. Any ideas on what to check?

 

[cheeseburgerhead69]

I would check the wiring and the bulb... May be the fender signals complete the circuit... Ground is important too... make sure everything is clean and your grounds are good

 

[F4R/T]

Grounds grounds! It could be in the column too but start simple and work your way back up to it.

 

[Hemirunner]

Disconnect the light socket from the housing, remove the bulb, check continuity from the socket to ground and then back to the turn signal switch output at the connector.
You could also bypass the flasher with 12v and check for voltage at the bulb socket. That might be easier, especially without help.

 

[70 Green Bee]

I agree with cheeseburgerhead and hemirunner...my left turn signal on my 70 Bee would work intermittently i.e. sometimes it would be on when lights were on, sometimes not; sometimes would flash fo turn signal, sometimes would not...swapped bulb, no change. So pulled it, cleaned the socket and spaces between the housing and bulb socket with electrical cleaner AND, put some solder on the joint between the socket and housing on the inside of the housing where the bulb goes...voila, it worked...so far, so good.

 

[MOPAR MARTY]

70 roadrunner. Trying to track down my last lighting issue. Brake lights, emergency flashers all work. Rear turn signals work. Right front amber turn signal flashes. Side marker and front/rear running lights work with headlight switch. However the left front amber signal does not flash. My hood marker turn signals are disconnected and the FSM diagram shows these hooked to the same circuit as the front amber lamps. But the right amber flasher works. Any ideas on what to check?

buy a new turnsingle switch it will solve the problem
trust me been there & dont that

 

[QOTHL]

70 roadrunner. Trying to track down my last lighting issue. Brake lights, emergency flashers all work. Rear turn signals work. Right front amber turn signal flashes. Side marker and front/rear running lights work with headlight switch. However the left front amber signal does not flash. My hood marker turn signals are disconnected and the FSM diagram shows these hooked to the same circuit as the front amber lamps. But the right amber flasher works. Any ideas on what to check?

The cheapest simplest thing to do first is check and or replace the bulb. I had new bulbs in my 69 Charger tail lights and because the problem was with all of the double filament bulbs on that side I blamed everything else. New bulbs, bad filaments, both of them. I had the same thing happen with a new set of in-hood turn signal bulbs. Both were crap.

 

[SlinktRR]

Thanks everybody these are great responses. I agree I think it is a ground problem. The bulb itself and turn signal switch are also concerns but I was able to test with a spare bulb verified flasher operation and continuity. I got distracted by a wheel bearing problem on my 8 3/4 but I remedied that, so now back to electrical. What I plan next is to do what 70 bee talked about, thanks man! The housing is pretty rough so that's my focus. Clean the socket out with contact cleaner and reinforce the ground contacts. Did you add solder to the bulb itself, or the slots in the bulb socket?

Has anyone added an extra ground wire to these lamp housings and if so where would you run it?

 

[Hemirunner]

buy a new turnsingle switch it will solve the problem
trust me been there & dont that

Very likely a possibility. I’d hate to drop the coin on the switch, go through the frustrations of replacing it and find out it’s something simple that didn’t get caught. In my case it was a fuse that I didn’t test with the meter. Been there done that.

 

[SlinktRR]

So the flasher and turn signal switch is definitely working and reaching the socket I verified with a multimeter, the voltage flashes when signal is engaged. Running lights work. Turn signal filament however doesn't light up. I've tried three bulbs. Nothing. Next I'm going to solder onto the bulb to improve the ground.

 

[70 Green Bee]

Slink sorry for the late response...no solder in the socket itself but a few spots around the joint of the socket and housing...will try to get a pic...

 

[SlinktRR]

I can't believe it took me this long to fix but ok, thought I'd update the thread in case someone has this problem one day. Over memorial day I installed a set of 1970 specific turn signal lamp housings from Roseville Moparts in Michigan. Great people there very helpful. The part is a really nice reproduction; it's not going to pass muster for a concours restoration as it is mostly plastic while the stock part was pot metal, but it looks and functions very well. Replacing the entire housing did the trick, so problem was likely ground for the OEM housing as it was badly rusted. I would definitely recommend these parts from Roseville.