13-burban

Ok so I've seen these posts and questions but I'm at an impass.

-Intermittent Engine hot AC turned off displayed on dash
-high fan turns on, temp gauge goes to zero
-I've replaced the thermostat 3x (ac delco), temp sensor 2x (ac delco), temp sensor pigtail, changed and flushed the coolant each time I replaced the thermo.

I'm beginning to suspect a gauge cluster or pcm issue.
Anyone Have a schematic with values for the coolant temp sensor?
I'm lost

2013 suburban 1500 LT
4x4
5.3l flex

repairman54

I would inspect the harness for damage. Use an electronic cleaner/lube on the ECM connections as fretting corrosion is common on all GM's in the late '00's and early teens.
I keep a can of DeOxit in my garage and spray every connector before they go back together.
The hot and temp to zero intermittent are a solid indication of an issue in the sensor circuit / harness. It's powered by only a 5v reference signal, so connections are critical.
My shop manual for my '11 has no specs listed for the ECT sensor.
alldatadiy.com will have the wiring diagram for your truck so you can identify sensor connections at the ECM plugs.