Need some help Electrical gurus!

[widowmaker77]

I’m almost done with my 66 build. 5.0
Explorer with c4. I’m running the centech harness and an 77 steering column. All my lights and turn signals work fine , HOWEVER if I Have the parking or headlights on the front blinkers won’t flash. Rear work fine and they both work fine if headlights are not on. Turn lights in front will not blink.
We were having issues getting any of the blinkers to work and traced that back to a bad new signal switch in the column from Tom’s . Installed old 77 turn signal switch that worked fine. Turn signals started working but now have issue described above. Any help is greatly appreciated.

 

[Oldtimer]

Check grounds.
Front turn signals & running lights are grounded to grill.
Headlights have a ground wire bolted to core support.
If grill has poor electrical contact with front fenders, turnsignal ground may backfeed thru headlight ground, untill headlights are turned on.

 

[widowmaker77]

Check grounds.
Front turn signals & running lights are grounded to grill.
Headlights have a ground wire bolted to core support.
If grill has poor electrical contact with front fenders, turnsignal ground may backfeed thru headlight ground, untill headlights are turned on.

Do the turn signal buckets ground to the grill?

 

[Oldtimer]

They are supposed to.
I added ground wires from the buckets to the core support on mine.

 

[widowmaker77]

They are supposed to.
I added ground wires from the buckets to the core support on mine.

Thanks! That may be my issue then. I painted all my panels separately then assembled , so the grill may not be grounded good to the tub. I’ll run a ground wire and see if that fixes t

 

[phred]

I wired a truck for a guy a few years back and had the same issue. Grounds were terrible. Everything, like yours was painted separately. I ended up putting a ground buss on the core support and grounded everything to it to get all the lights to function properly.

 

[widowmaker77]

I wired a truck for a guy a few years back and had the same issue. Grounds were terrible. Everything, like yours was painted separately. I ended up putting a ground buss on the core support and grounded everything to it to get all the lights to function properly.

I ran several grounds from the frame to the body and frame to the engine. Didn’t think about one to the grill. Didn’t realize the parking/blinker lights ground through the grill to the body.

 

[Viperwolf1]

When you get tired of chasing grounds, you might take a closer look at the actual filaments in the bulbs. If the dimmer filament is connected to the turn signal, you won't see it flash when the brighter filament is lit. Very common problem with new turn buckets.

 

[widowmaker77]

When you get tired of chasing grounds, you might take a closer look at the actual filaments in the bulbs. If the dimmer filament is connected to the turn signal, you won't see it flash when the brighter filament is lit. Very common problem with new turn buckets.

Thanks viperwolf. I’ll be sure to check that also

 

[jerry]

This may sound a little odd, but I had problems with my turn signals after installing a new painless harness. For me the problem areas were: The ground wire at the fuse box was not attached, and the ignition switch was not grounded (I had it out and loose still).

Once I fixed those I was good to go.