Only 1 evaporator on the car. Try turning on the ac and holding down the REST button for 5 secs. Your display will change to a diagnostic one. The numbers run from 1 -41 but many are missing.
1=inside air temp
2=ouside air temp
3=left hearter core temp
4=right heater core temp
5=evaporator temp
7=refrigerant pressure in bars

You got through the numbers by pushing the auto button on the panel. Left side auto increases the # and right side auto decreases the #.

If your temp sensors are bad in either the left or right heater core it could be your problem. To check for this, leave the car sit for a few hours and power the electric system without starting the engine, hit the REST button and go through the sequence to get to #3 and #4. If the sensors are OK they should read the same or very close. If they are far off, you have a bad sensor.
Hope this helps.

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