It sounds like you have a bad transmission gear range selector switch that is bad and needs to be replaced, here is a a diagrams (below) that will help you get the job done.
They call it a neutral safety switch but it does a lot more than telling when the transmission is in neutral.
To be sure though we can do some wiring tests. Here is a guide and wiring diagrams to help.
Please check the fuses as well.
Please let us know what you find.
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Thursday, September 7th, 2017 AT 12:50 PM