For my 2004 Chevrolet Trailblazer, what is the most probable cause of engine code P0597?

Question

For my 2004 Chevrolet Trailblazer 4.2L, what is the most probable cause of engine code P0597?

Answer 1

The thermostat is the most likely cause of the problem.

P0597 Chevrolet Code - Thermostat Heater Control Circuit Open
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