Heat Exchanger Solenoid. Short to B+
Heat Exchanger Solenoid. Open Circuit / Short to Ground
Perceived temperature in cabin too high or too low compared to the set temperature.
The following conditions apply:
• A short to B+ is indicated when the output for the heat exchanger solenoid is activated and the voltage on pin 24 exceeds 6 V.
• A short to ground is indicated when the output for the circulation pump is not activated and the voltage on pin 24 exceeds 6 V.
• Measured every 440 ms and 5 consecutive measurements are required to set a diagnostic trouble code.
• The diagnostic trouble code is cleared after the ignition has been turned on 20 times and the malfunction conditions have not been fulfilled.
• When the diagnostic trouble code has been set the output is switched off.