Security lock? Engine will not turn over?

2002 CHEVROLET IMPALA
1,300,000 MILES
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KEVIN BERGEMANN
  • MEMBER
  • 1 POST
Car won’t turn over. I replaced the ignition lock switch. Went through the relearn process no luck. Next replaced the BCM did the relearn process again and no turn over. Checked the started it’s fine. The battery is good also. What should I do next?
Apr 27, 2023 at 10:45 PM
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STRAILER
  • ✓Experienced Mechanic
  • 55,254 POSTS
When you try to crank the engine over does the security light flash? If not, I would swap out the crank relay and try to crank the engine over in neutral. Here is a guide to help you check for power and the starter wiring diagrams so you can see how the system works:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

This guide may help as well:

https://www.2carpros.com/articles/starter-not-working-repair

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Apr 29, 2023 at 4:43 AM
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