I assume the vehicle is overheating? Do both fans come on when the A/C is on?
Also, we need to check power coming from the PCM when the engine is at operating temp. This could be as simple as a temperature sensor or more complicated like a PCM.
However, let's start with checking power on the command terminal of the relay. Check this by removing the fan control relay one and two then put the positive lead of the positive battery post and then the black lead on the terminal from the relay when the fans should be on. If there is 12 volts then the PCM is grounding the relay and the fans should be on.
Let's start there and see what we turn up.
Image (Click to make bigger)
Saturday, September 19th, 2020 AT 6:30 PM