Compressor Control Relay
The compressor clutch coil is energized through the compressor control
relay. This relay is activated by the PCM in A/C modes. The PCM provides cut-off
of the relay under certain operating conditions such as wide open throttle.
A/C Refrigerant Pressure Sensor
The electronic A/C refrigerant pressure sensor is mounted to the line
between the condenser and the evaporator. The output to the PCM is variable.
The output of the PCM depends on the pressure inside of the line. A higher
pressure will result in a higher voltage output.
The PCM constantly monitors the A/C system pressure in order to achieve
the following effects:
• | Disengage the A/C clutch if the pressure is above 2700 kPa
(440 psi). |
• | Disengage the A/C clutch if the pressure is below 285 kPa
(38 psi). |
• | Boost the idle air control in order to compensate for the A/C
load at idle. |
• | Control the cooling fan operation. |
| Refer to Electrical Cooling Fan Diagnosis. |
Replace the pressure sensor if the pressure sensor fails. The pressure
sensor is not repairable. Refer to LINK.