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Old 03-02-2026, 09:47 AM   #7
glennpm
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Default Re: testing for the existence of ballast resistor in my car

Quote:
Originally Posted by hueyhoolihan View Post
ah!!! i think i see...

assuming the resistor is cold, when i turn on the ignition switch the resistance will be at it's lowest and steadily increase as time passes. can we assume that to make a second test, one would have to wait for it to cool down? and can i assume that it cools very quickly indeed, such that once the voltage is removed, restarting these cars BITD was not problematical?
As you mentioned, DON’T use the resistor with a Petronix module.

When starting with points, the resistance is very low and helps when starting. Once started, the resistor heats up increasing resistance and protecting the points from burning.
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Last edited by glennpm; 03-03-2026 at 10:19 AM.
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