Car dies when using indicators or when brake light turns on.

[Newkidonthebloc]

Hey Everyone,

Currently the new season is almost starting and after working on the car all winter I only have one electrical issue left that drives me absolutely nuts. I've cleaned up a bunch of grounds and are at a loss atm. I hope the more experienced B body owner can help me out/ or give me an idea where to look. I will describe the problem I am having and follow that by a few questions I have.

This problem randomly started occurring when I drove back from a longer trip. Once I use the indicators there will be a small pause. Once the relay starts clicking the lights are turned on and simultaneously the car seems to lose spark for a split second. If you are driving, the momentum will allow the motor to pick up again and you will feel a slight hiccup. However, when stationary the hiccup is sufficient to stall the motor. This happens every time a new circuit is closed or something starts to draw power. I say that because I also noticed that I could cause these hiccups by opening the drivers side door and turning the interior lights on. Same story for the headlights

What I found looking for the problem:
- The dash lights dim slightly every time the turn signal is on. Same goes for the interior lights.
- cleaning up engine and ignition grounds did not help
- coil is good
- replaced ballast resistor
- altenator is charging
- Battery was old and tired. After starting a couple of times due to the issues described above the battery wasnt able to turn the engine over anymore. I have ordered a new one but I dont think it is the main culprit (if it is let me know tho).


If anyone has had this problem before and knows what is going one please let me know.

Q: Is there an additional ground connection for just the dash/steeting collumn?


Best,

Thom

 

[Photon440]

I'd start by putting a voltmeter on the ignition wiring, both distributor and coil, and seeing if the readings fluctuate when turning on the signal lights.

 

[PurpleBeeper]

It "sounds" like you might have a short (exposed wires) coming from the turn signal switch and/or ignition switch leading down to the two big plugs at the bottom of the steering column inside the car. The connectors often get hot & melt too.

 

[WileE]

Trace and isolate your primary ignition circuit.

 

[Newkidonthebloc]

I have tested a couple of things with a new battery in place. Ign switch was good. Coil had power with ign switch on. However, during testing the whole turn indicator part stopped working for some reason. I have ordered a new relay and switch. Will continue searching for the problem once I have those back up and running.

 

[Xp29h]

Grounds?

 

[Newkidonthebloc]

Grounds?

I would expect flickering or the lights not working entirely if the grounds are bad. The stutter only occurs when a circuit is closed. Once one of those circuits is closed, the car operates like normal again. Nevertheless, I plan to check the grounds on the tail light and of the ignition system circuit. The engine ground is fine. I replaced the ground strap and put new connections on all grounds going to the block.

 

[1967coronet]

One of the problem areas in these old Mopars is the bulk head electric connections at the fire wall.
Over time they build corrosion and cause problems.
Clean them up with a brass brush and some electric contact spray cleaner and add some dielectric grease.
If the contacts are real dirty you may need to release them one at a time clean and replace.
Like posted above double check all grounds.
Also check your fuse block for corrosion and the correct size fuse's.
One other possibility is a aftermarket turn single switch installed and now shorting out.

 

[Newkidonthebloc]

One of the problem areas in these old Mopars is the bulk head electric connections at the fire wall.
Over time they build corrosion and cause problems.
Clean them up with a brass brush and some electric contact spray cleaner and add some dielectric grease.
If the contacts are real dirty you may need to release them one at a time clean and replace.
Like posted above double check all grounds.
Also check your fuse block for corrosion and the correct size fuse's.

The car came with an aftermarket wiring harness (EZ wiring). However due to the way they installed it I have to pull the dash to get access to many of the wires/connections that I fear being the culprit.

 

[1967coronet]

The car came with an aftermarket wiring harness (EZ wiring). However due to the way they installed it I have to pull the dash to get access to many of the wires/connections that I fear being the culprit.

Ok, I hear that.
before pulling the dash ect. Pull the steering wheel and check the wiring at the turn single switch.
Hope you track the problem down.

 

[Newkidonthebloc]

Ok, I hear that.
before pulling the dash ect. Pull the steering wheel and check the wiring at the turn single switch.
Hope you track the problem down.

I already did that, found quite the mess. I already knew the cancel cams were broken off. This was the last push to me getting a new switch. However, the fact that it also happens sometimes when the brake/interior lights are turned on leads me to believe the problem is more general. BTW I also ordered a new turn signal relay and ign switch to rule those out aswell.

 

[Doorkicker]

The car came with an aftermarket wiring harness (EZ wiring). However due to the way they installed it I have to pull the dash to get access to many of the wires/connections that I fear being the culprit.

I just want to backup what @1967coronet said. I had a recent issue - different but fundamentally similar - and it was two things... the ground strap from the engine to the firewall needed replacing. Looked great, great solid connection - not working. The second thing was the ground from the batt. to the block. I remounted that and added a gound wire from the batt. pole to the body. Now, this was for a completely different issue, but the similar part was weirdness.

One thing I would check is volts to ignition while cranking. There are 3 (or 4) wires. If one of those has an issue, say crossing over in the column... you will absolutely get what you're describing. Keep in mind that the turn signal switch is involved in all kinds of things other than turn signals... such as brake lights. Also, common ground is tied into the the dome switch in the doors.

Do you have the stock wiring diagram? I know you said you're running an aftermarket harness, but you can still verify.

 

[Xp29h]

I would expect flickering or the lights not working entirely if the grounds are bad. The stutter only occurs when a circuit is closed. Once one of those circuits is closed, the car operates like normal again. Nevertheless, I plan to check the grounds on the tail light and of the ignition system circuit. The engine ground is fine. I replaced the ground strap and put new connections on all grounds going to the block.

I had some really weird crap going on with my car prior to the rewire. I thought with grounds you might get the flicker or the intermittent or not work at all. I got the complete stay on, the weird blink if you could call it that. The engine cut out and a bad ground caused my first mad to completely go nuts and stop working all together! These old cars go nuts with bad grounds. I think back in the day with older parts, they were more predictable but adding parts made years later can cause some serious headaches. My car is now grounded everywhere and well. No issues now at all!

Always a good double, triple check for grounds especially with older wiring and systems.

 

[Newkidonthebloc]

I just want to backup what @1967coronet said. I had a recent issue - different but fundamentally similar - and it was two things... the ground strap from the engine to the firewall needed replacing. Looked great, great solid connection - not working. The second thing was the ground from the batt. to the block. I remounted that and added a gound wire from the batt. pole to the body. Now, this was for a completely different issue, but the similar part was weirdness.

One thing I would check is volts to ignition while cranking. There are 3 (or 4) wires. If one of those has an issue, say crossing over in the column... you will absolutely get what you're describing. Keep in mind that the turn signal switch is involved in all kinds of things other than turn signals... such as brake lights. Also, common ground is tied into the the dome switch in the doors.

Do you have the stock wiring diagram? I know you said you're running an aftermarket harness, but you can still verify.

Thanks for your response! Yeah I have the original wiring diagrams from the service manual, the EZ wiring harness, and the one for installing the MSD distributor. Redoing the body ground was the first one on the list for this weekend. Will start measuring and following the wires related to the rear lights all one by one. After that I will install the new switches and turn signal relay. After that, I only need to find another person willingly to turn keys/ turn signal post while i am out in front with the multimeter. Once I have done all that I will report back to every one.