Hello I'm Neal and I am here to help resolve your issue. If I cannot help I will opt out and refer your question to another expert.
Do you mean the fuel pump relay?
is there a relay switch on a 96 tahoe?
Yes there is. The Fuel Pump Relay is located in Underhood Fuse Relay Center. The Underhood Fuse Relay Center is located on the LH rear of engine compartment, on fender. Here is a diagram.
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