Circuit Description
WARNING: This page is about a different car, the 2008 Suzuki Swift +, 2008 Pontiac Wave, and 2008 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.
The air conditioning (A/C) refrigerant pressure sensor is used by the engine control module (ECM) to monitor the high side refrigerant pressure. The A/C refrigerant pressure sensor utilizes the following 3 circuits:
- A 5-volt reference circuit
- A low reference circuit
- A signal circuit
The ECM monitors the signal circuit voltage. If the A/C high side pressure is high, the signal voltage is high. If the A/C high side pressure is low, the signal voltage is low. The ECM uses the voltage readings to determine the operation of the A/C compressor and the cooling fans. If the ECM detects an excessively high or low signal voltage, a DTC sets.