I am trying to disconnect the security system but do not know how to do so
My car has 130000 miles.
My car has an automatic transmission.
Hi there - your GM car uses a "raised chip" key security system which can have problems with age. The ignition tumbler has a "reader" for the raised contact area of the key. The reader or the 2 wires going to it can fail over time, resulting in a ’no start’ condition as you are experiencing. Try using a different, known good, key. If that doesn’t work either the key reader is the likely problem, and must be replaced. Unfortunately, this is not a service YourMechanic can provide at this time. Your key needs to be service by a locksmith or GM service center, who will replace the ignition tumbler and reader.
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