2008 trailblazer coolant temp sensor

[zora]

please explain in detail what your issue is and if you have a check engine light on, what are the codes?

[Hunain]

From last month it’s happened frequently that temperature indication goes with A/C after driving few KM’s check engine light is on. I continue to remove battery terminal to reset and it drives for couple of days. But from last week after resting from the battery terminal the temperature indication suddenly goes off within 5km of driving.
I take it to garage he removes the radiator and clean it with chemical replace water pump. After one day today drives around 50km in the afternoon that time it was ok. But while driving back in the evening with low ambient temperature indication goes down again, i continue driving but this time no check engine light. Earlier I visit the dealer they scanned but not found any codes.
Thanks for noticing

[Hunain]

Temperature sensor is replaced already
TIA

[zora]

have you used an IR gun to determine what the actual temperature is, which if very low would mean the thermostat is stuck open.
why did the mechanic remove the radiator and clean it and also replace the water pump, was the engine overheating?

[Hunain]

Today I scanned after getting the check engine light and got the code P0128.
And I already replaced the temperature sensor.
Please advise me what to do now
Thanks

[zora]

the first thing the code listing tells you to do is replace the thermostat not the sensor. Did you replace the thermostat.

https://www.obd-codes.com/p0128

[Hunain]

Today I replaced thermostat with new one and during test run of half hour temperature indication remains ON but the temperature was more. It reaches upto 100 on the gauge. Is it normal running temperature?
Right now the ambiant temprature is 27 celcious. But in summer it reaches upto 45 celsious.
Thanks

[zora]

you replaced the thermostat with a 195 degree thermostat?
if you did install a 195 thermostat normal temperature is 195 to about 220.