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Q: Security system disabled start

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My yukon denali won't start from time to time. Normally if no start, I'll wait 10 mins or so and try again till it does. The security light inside will blink constantly and now will not turn over for a few days now. I am 99% sure it has to do with the security system (vats) and only have 1 key. When it does start, it starts like new. This time I'm out of luck and time. I'm a disabled combat veteran and dont have the funds to bring it in anywhere. I'm looking to fix this asap because this is my only vehicle. Any help would be appreciated especially a detailed way to pass lock like they do on YouTube. Thank!

My car has 215000 miles.
My car has an automatic transmission.

A: If the starting problem was there all the t...

If the starting problem was there all the time, then it would most likely be the body control module. But since this is an intermittent problem, then you may have connections issues to the body control module or ignition vats module. I would recommend disconnecting the battery and disconnecting at the modules and adding dielectric lube to the pins. After, reinstall the connections and reconnect the battery. If this cures the problem, then you had a connection that was causing too much resistance and a voltage drop in the system. If the problem continues, then the body control module may be causing the problem. The connection issues are more common. If you are looking to have this checked, a technician from YourMechanic can come to your car’s location to diagnose your car’s starting issue and perform any needed repairs.

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