Coolant Temperature Sensor G62, Caddy 06, 1.9 TDI BLS

Hello.

After the engine warning light came on in my Caddy, I took it to the dealership. They read the error codes, and the error was: coolant temperature sensor G62.

He deleted the error code and said that if the light comes on again, the sensor needs to be replaced.
The light came back on a bit later. So, I went back to the friendly seller, bought another one, installed it (without clearing the error memory, as I don't have the means to do so). The light initially stayed on, but after a few driving cycles, it finally went out. Also, the engine no longer revs briefly during a cold start, and the fan no longer runs when the ignition is on in a warm state.

Two days later, the light turned on again .

My question is whether the 1.9 BLS engine has two (physical) sensors, and whether these sensors are identical (have the same part number). (The temperature gauge has been displaying correct and plausible readings the entire time.)

I replaced the sensor at the front of the engine; it's easily visible when you open the hood.
'However, I think I saw another one on the left side of the engine (facing forward), possibly near the coolant distribution pipe. Is that the same sensor? Should I replace that one too?'

Thank you for your help!

Regards,
Crissi.

Could this be an emissions-related error that needs to be cleared to prevent it from recurring?