2005 Chevy Silverado Engine Temp

At normal operating tempreature the reading should be about 210 on the gauge. Does the gauge read 160 when it should be up to temp?

Thank you for the reply. Yes. When I first start the vehicle after driving to operating temp, the gauge will go up and then fall back to 160. This happened all of the sudden. No warning. A little background, the check engine light cam on yesterday, the compas/temp display on the rearview mirror started to cycle on and off, and the amp gauge was at 12 (or less). I replaced the Battery in the vehicle yesterday (dont know if it had anything to do with it)and the temp gauge issue started.

Do a complete charging system test and verify the alternator output is in range. Did the voltage come back up with the new battery?

We know that the temperature isn't going to "actually" drop 50 degrees in an instant. So obviously there is a continuity or component malfunction. You can verify this with a scan tool connected to the vehicle at operating temperature. There is an Engine Coolant Temperature sensor for the PCM and a Temperature Sending unit for the gauge.

If the scan tool displays 200-210 we know it's the sender to gauge circuit, the sender or the gauge.