Tell me about your ballast resistor failure.

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cruiser

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Guys: I'm interested in learning how many of you have had a ballast resistor failure in your ride. What happened when it failed? Did everything die, or just the ignition system? How long did your ballast last before it failed. How did you know it failed? Any and all inputs welcomed. Thanks!
 
I used to carry extras in the glove box in my youth. They failed pretty frequently in the 70s.

When they fail, the car will start, but as soon as you let off the key it will die.
 
I always carry a spare in the trunk along with a electronic ignition control unit, leaving the ignition on seems to be hard on them they get really hot.
 
This is all overblown. I've only replaced one or two since my first 69 RR I bought in 70. I've known lots of Mopar owners through the years, and many of them didn't know WTF a ballast WAS. I think the biggest failures are caused by 1...folks leaving the key in "run" or using "run" to operate the radio instead of "accessory" when stopped, or 2...water breaking the ceramic, road splash, rain, etc, and then at some point, vibration finishes the job
 
Yep.
The original ballast resistors failed frequently. Most Chrysler products that got towed in to the shop I worked in as a kid, needed a ballast resistor.
It was commonplace after a good rain, some cars, with bad hood gaps, that got wet alot, would actually crack.
I havent seen that many short out like years ago, not sure if they beefed them up internally.
But the ones that didnt start, just cranked, as soon as you swapped out the resistor, they fired right up. Like clockwork.
 
Car would start drive a mile and shut down. Wait 15,20 minutes and it would start again, another mile shut down. Turn over start and when I released the key it died until it cooled down for 20 minutes. Always, always, carry a spare.
 
in middle seventies I had a 68 charger that would pop one every 3-4 months. car would be running good then lights would start flashing off and on and 5 minutes after that car would die. You could crank it forever with zero interest in starting. replace ballast resister and go for another 3-4 months. I was 16 and they were cheap so I just replaced. Now I would dig into what kept popping them. I have owned lots of mopars since and never had any others go out on me.
 
53 years and 319,000 miles on the same ballast resister. The resister even has a crack in the dowel that the wire is wound on.
 
I've had bad ones but I cannot really say what happened on any car I had that I experienced a bad BR as I just replaced it and moved on. That said, it definitely was not a "common" thing even back in the day (talking about the mid-late 70's and early 80's, at least for me and those I ran with.
 
I built a 76 power wagon and drove it to Colorado and gave it to my son... I told him for months to put a ballast resistor in the glove box.. he didn't... I flew out to visit him and my grandchildren... I brought a ballast resistor and told him I put it in the glove box...
Six months or so later I get a call from my son on his way to work in his Honda...
He said he was going to take the truck to work but when he went to start it it turned over fine and wanted to start but wouldn't.. I said did you try the ballast resistor I put in the glove box?.. NO..
Later that afternoon the text came in.. "damnit dad..." It fired right up...
 
We always kept one in the glove box nearly 50 years ago also and we used them at least twice. Now that I think about it, they were used ones from the junkyard. And, of course that's because we didn't have much money back then. Maybe they weren't as bad as we thought they were. Lol
 
I have replaced 2 in 30 years one after hitting a huge puddle at speed, it cracked, and the other when I finished my Dart...after doing all that work and replacing the engine bay wiring harness there was no way I was putting the old one back in.
 
When the ballast resistor goes bad, it won't start.... :(
 
I've had a few fail over the years.What I discovered early on before I really knew anything about how they work is that if you hold the key between the run position and the start position it will run so I got off the road that way. I always carry a spare in all my cars and even showed my wife how to do a quick change of one on the side of the road if one fails in her car . Don't leave home without one !
 
I have had 2 go bad since the 70's. First one puzzled me and took us a few minutes to remember, lol. 68 Barracuda in about 1978 on my way to a concert stopped at a store for supplies and turned it off. Hopped in, turned the key to start fired right up, release the key and it quit.
 
I put a spare in the glove box of my 80 power wagon, its still there. It would quit occasionally, when damp outside. Rotor had a burn hole in it. First time i ever saw that. Spare rotor with ballast.
 
I think they fixed the problem in the 80s, so they rarely fail anymore. However, having been traumatized by the failures in my youth, I still carry a spare in my cuda.....haha.
 
Usually the wire that is wrapped around the ceramic rod burns through. This is a points style. I know I will get a ton of remarks on this but it is usally the wrong value for the system. Best bet is look in the FSM in section 8 for the value. Here are some for the ECU box for example.
ECUApplication.jpg
ECUApplication.jpg
ecuII.jpg
ecu III.png
ECUApplication.jpg
ecuII.jpg
ecu III.png

7c36fbad-c7ac-4b2a-94be-fb9b3d890d52_1.16c64ec55acd81ce4a30bd7db7543cad.jpg
 
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Guys: I'm interested in learning how many of you have had a ballast resistor failure in your ride. What happened when it failed? Did everything die, or just the ignition system? How long did your ballast last before it failed. How did you know it failed? Any and all inputs welcomed. Thanks!
Once. First car, about 1981. '71 Charger. Typical symptoms, crank/start but no run.
 
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