ballast resistor problem

[beerboy]

i have 2 ballast resistors blow in the last 3 weeks drive the car roughly once a week . always carry spares and dont leave key in ignition when parked. orange USA MADE ECU going maybe? car starts and runs fine then park it , go to start just cranks put another new resistor in and cranks but no start. could the resistors being from overseas be the problem or ECU GOING?

 

[RedFish]

The first thing I think of is moisture. Your suggestion of poor quality is possible.

 

[Oldmanmopar]

Is it over charging while driving? Sending to much voltage to the 12 volt side. Then gets hot and when cools cracks the internal winding.

Did you try another coil? See if the coil is hot after a ride Coil might have lost its fluid.

 

[toolmanmike]

What ignition system are you running and what resistance are your ballast resistos?

 

[Dana67Dart]

Assuming you have a 4 pin ECU...

The ballast only feeds the coil.

If you have other devices connected to the coil side of the ballast that could do it.

If you have a super duper wamo coil that draws extra current that could do it.

Check your wiring to be sure you don't have an intermittent short.

Also check that the ignition is actually shutting off power to the ballast

 

[67Dart273]

Overcharging is a good bet, and so is defective coil.

Maybe something is mis-wired. Has anything been added to the "ignition run" circuit?

Might try to find another parts source / supplier, and then make certain that the next one--or two--are actually different from the first two.

 

[Bewy]

How did you determine that the bal res blew?

 

[Kern Dog]

 

[Dana67Dart]

How did you determine that the bal res blew

Remove it from the car. Visually inspect it. Take an ohm meter and check for continuity, while moving the terminals around to check for an intermittent open.

It should read .5 to 1.5 ohms check your Factory Service Manual OR what the coil manufacturer says.

 

[beerboy]

car has never been in rain or wet weather always garaged. its a 4 prong out of a 73 duster. we went to a store not far at all. we were gone maybe 25 minutes cranks but no start , change to the spare resistor --brand new and starts right up, i have been to cruise nights where the car sat for 2-3 hours and never a problem , that would give a cool down time .i will do some testing and check the coil,coil or resistor maybe getting to hot; like i say i very rarely drive the car for a short stint then go to start it till i am home which tells me it could be a heat problem . car is driven brought into my garage shut down then runs again a few days after

 

[68Bee]

Best guess is crappy resistors.

 

[67Dart273]

car has never been in rain or wet weather always garaged. its a 4 prong out of a 73 duster. we went to a store not far at all. we were gone maybe 25 minutes cranks but no start , change to the spare resistor --brand new and starts right up, i have been to cruise nights where the car sat for 2-3 hours and never a problem , that would give a cool down time .i will do some testing and check the coil,coil or resistor maybe getting to hot; like i say i very rarely drive the car for a short stint then go to start it till i am home which tells me it could be a heat problem . car is driven brought into my garage shut down then runs again a few days after

NOW you tell us. You NEED to tell people "the whole story" and the year make model. ALWAYS

1....A 4 pin is only needed if the ECU is the older "5 pin" box. You can NOT tell if a box is 4 or 5 pin by looking at the connector. Some newer, 4 pin poxes have 5 physical pins. Have you CHECKED CONTINUITY of the resistor?

2...Make CERTAIN the resistor is wired correctly, as they are actually two DIFFERENT VALUE resistors. The "U" cutout on one end is to correctly orient the assembly in the connectors, so that it has the correct value resistor to the correct circuit.

3...IT IS POSSIBLE that you have a problem in the bypass circuit rather than the resistor itself.

HOW HAVE YOU determined that these are bad?

 

[beerboy]

correct resistor and correct ecu box, still testing things. sorry about not giving make and model

 

[CRUZE 418]

What I read here on the run and no start, in my case, has always been the coil. Make sure that you get the correct ohm coil.

 

[Dartswinger70]

Uh Oh...

 

[Dana67Dart]

An easy test of the ballast is bring a jumper wire with alligator clips on the ends, next time it doesn't start clip one lead to coil positive the other to battery positive. Then try starting.

If it starts and runs pull the leads off, if it continues running it's not the ballast, but it might be the ignition 2 cir not providing anything or enough to the coil during startup to get it to fire.


Check that the resister values are correct for your application. And you have it hooked up correctly

 

[Mattax]

Just because its on the internet does not make it right. Or right for the application in question.
1973 Dodge Chassis Manual. page 8-121

 

[Dana67Dart]

Just because its on the internet does not make it right. Or right for the application in question.

agreed

Check that the resister values are correct for your application

 

[Mike69cuda]

The good ballast resistors are potted on the back as I recall…….

But maybe I misremember….