Faulty ECT Sensor, VAS Codes

[A4WAGON]

Hey forum members, need technical advice. Just replaced Timing Belt and WP - and during service fault codes
17700/P1292 and 19497/P3041 came up - and further event info listed 1039 ECT Sensor G2, open/short circuit to B+, sporadic.

Ran my own tests, driving car, the temp gage is not consistent, went from cold to mid way (normal) and back.
Checked temp with infared thermometer and temp was consistent, after driving for 30 min; and after car had been off for an hour, tested again, after warm up.

can you just change the thermostat sensor? or do you also have to change the thermostat?
thanks

 

[madmike01uk]

You need a new CTS from the sounds of it.

 

[A4WAGON]

have cleared codes. And gauge did erratic stuff again - but when I had codes checked again, there was not any error code. It was suggested that perhaps it is the stat then. Does that make sense? Just dragging my feet having to do both, and find out whichever I pick to do doesn't work.... Any one in the forum have ideas - i see many threads suggesting change stat first, cause it is easier...