Exterior lighting issue

[dickey_440]

I have been reading previous threads on this topic to avoid starting another one. I have also tried several of the reccomendations discussed, but I'm am still having problems. Car is a 73 dart swinger 340. The issue is the blinkers. They work fine when the headlights are off (other than the passenger side hood indicator. It was dull, I replaced the bulb now it doesn't work at all.) the passenger side front blinker is also always dull. I have checked the two grounds I have found(drivers side radiator support and one in the trunk.) both seem to be good. I installed a new blinker flasher. Sounds better and both sides seem brighter, but right is still slow and dull. All the fuses look good. Also when the lights are on the right turn indicator on the dash stays on. Lastly the license plate light is extremely dull and one of my reverse light sockets is rusted out/lost spring tension. I have very little electrical knowledge so any help would be great!

 

[mcnoople]

Use a voltmeter at each of the sockets in question to measure across the terminals. With the vehicle running and the light turned on you should see a measurement very close to battery voltage. If you get a reading that is lower than what you measure at the battery by .5v or more then you have a definate problem.

Next take the voltmeter and attach 1 terminal to battery ground and the other terminal to the pin in the lamp socket. If your reading goes up (more volts measure) then you have a ground problem.

Another method that might be somewhat simpler is. Run a piece of wire (temporarily) from the NEGATIVE battery terminal to the ground for the passenger side turn signals ground. If the bulb is no longer "slow and dull" then you have a ground problem. Other likely culprits are dirty/corroded lamp sockets and the infamous bulkhead connector.

 

[RedFish]

"right turn indicator in the dash stays on"
That clearly shows a fault with ground in the right front fixture. Even though the ground wire is sucured to the chassis the ground is lost before it gets there. The bulb sockets rust inside. The spring behind the contact board should push the bulb tight against the 2 tiny keepers on it and create a ground path there. Not much huh ? Well, I didn't design the things, sorry.
In a more perfect world the bulb and its socket would be a little more egg shaped so there would be more contact between the base of the bulb and its socket wall.
Clean the socket interior well, invest in premium bulbs with nickle coated bases.
The best bulb replacement on the market comes from the Honda dealership. I dont have their part number handy.
Happy moparing

 

[67Dart273]

"right turn indicator in the dash stays on"
That clearly shows a fault with ground

X2. I'd pull all sockets, front and rear, clean or replace, replace pigtails if they look bad, and clean or replace the bulbs.

Don't be afraid (if you can solder) to attach ground pigtails to the socket shells so that you can ground them well. For the tail lights, you can run an additional wire from each one over to the trunk latch bolts

 

[dickey_440]

Thanks for the advice. It was a bad ground at the front passenger turn indicator. Everything is working great now. Also, for future reference, can anyone reccomend a place to get some good replacement sockets?

 

[RedFish]

More modern designs have the sockets inserted from behind the fixture. There is a lot of time and money involved in any update. In most cases a good cleaning, a little di-electric grease, and new gaskets at the lenses will add years life to your OEM .