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Old 01-12-2019, 10:19 PM
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andrewwynn andrewwynn is offline
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Quote:
Originally Posted by DaveX53.0i View Post
Not the key, both have the same issue. If it were the ignition switch wouldn't my accessories not work? and wouldn't it not always start with a jump? Also when it won't start, voltage at the B+ is very low, below 1.


Incorrect. When an ignition switch fails the most common symptom is that you get inconsistent starts. There are several parrallel switches inside the switch and the starter switch component is a common failure point and exhibits exactly your symptoms when it fails.

That being said, B+ volts low means battery problem. If B+ is low then it's not logical it would ever recover from that and start without a jump unless you have a connection problem somewhere.

If you have a defective battery it can cause very quick drops in battery voltage. I had a battery that would test fine, 550 cold crank amps, start the car at 0°F more than once no problem.

However, if I left the hazards blinking for 8 minutes I would not be able to start the car I would get one click. At that point I would get a very low vBat and would jump start easily.

My case turned out to be a defective battery (shorted plates or something: it effectively had nearly no AH capacity)

New battery fixed it right up
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