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Q: Installed a new ignition harness after the old one required repeated key giggling to start the car, now won't start

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First I installed a PCM ignition relay board successfully and then found out it was the ignition switch harness that needed replacement. I installed an Autozone harness and now the car won't start. It turns over fine and the dash lights work put won't start. I suspect something to do with the immobilizer because the door alarm no longer activates or sounds off. Not sure why when I did not replace the actual mechanical key switch tumbler and I never removed the immobilizer and I'm using the original key. I re-installed the old harness that did work with a giggle or two first and now it no longer works...the car still won't start. My issue is the car has a aftermarket stereo and I'm unable to locate the security code/reprogram number that was in the glove box. Please help. Mel

My car has 130000 miles.
My car has a manual transmission.

A: When you replaced the harness you made the ...

When you replaced the harness you made the immobilizer lose its memory. The car is not starting because it needs to re learn the key values. I recommend having the vehicle checked by a certified mechanic to verify the cause of the starting issue. A technician from YourMechanic can do a thorough diagnosis and help you successfully relearn the immobilizer if you need assistance.

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