Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. How Long Does a Ballast Resistor Last?

How Long Does a Ballast Resistor Last?

ballasts resistor

A ballast resistor is a component in the ignition system of older vehicles. If you drive a classic, you are familiar with coils and points. You don’t have an onboard computer, and obviously you don’t have circuit boards that can control the voltage when you start up your engine. This is where the ballast resistor comes in. It is actually something like a huge fuse that is located between the positive battery cable and the ignition switch, and it works to lower the voltage that is delivered to the coil so that it doesn’t burn out. When you crank your engine, the ballast resistor ensures that the normal battery voltage is delivered to the coil in order to start the engine.

If the original ballast resistor is still working in your classic car, then you are a very lucky driver. Because the ballast resistor takes so much heat during normal operation, it is vulnerable to damage and will eventually wear out. How often you drive could be a factor, but there is no specific “best before” date. The ballast resistor could last for many years, but it does take a lot of wear and tear, and it could fail suddenly. Your ballast receiver needs to be replaced if the engine cranks but stalls as soon as key is returned to the “run” position

If your ballast resistor fails, you will have to have it replaced. Resist the temptation to listen to well-meaning classic car fellows, who may suggest jumping the resistor. If you do, your points will ultimately burn out, and you will require expensive repairs. A professional mechanic can replace the ballast resistor and have your beloved classic running properly again.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...


Related questions

Q: Air conditioner

When you wiggle the green wire, it allows power to get to the blower motor. You should disconnect the connector for the resistor and blower motor and check the connector for signs of overheating, rust, or corrosion. Repair or...

Q: my headlights are not working again.

Hi there. If the headlights are burning out a few days after replacing them, there could be an electrical short in the wiring for the lights causing them to overheat or the ballast resistor is not working causing the headlights...

Q: Engine shut off while driving

Electrical resistance increases with heat. Somewhere in an electrical circuit (ignition coil, fuel supply, etc.) the temperature reaches a point where the resistance creates a large enough voltage drop that the engine (controls) shut down. I would check the coil...