Diagnostic Table
WARNING: This page is about a different car, the 2004 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
- Refer to the chart below. See DIAGNOSTIC CHART .DIAGNOSTIC CHART
High (Discharge) Pressure Low (Suction) Pressure Component - Causes High or clutch cycling High Condenser - inadequate airflow. High Normal to high Engine - overheating. Normal to high Normal Refrigerant overcharge - air in refrigerant. Normal to low High Thermostatic expansion valve Normal to low Normal to high A/C suction line - partially restricted or plugged (1). Normal to low Low or clutch cycling Low refrigerant charge, A/C suction line - partially restricted or plugged. Erratic operation or compressor not running Evaporator discharge temperature sensor - poor connection at A/C clutch connector. A/C electrical circuit erratic - see A/C Electrical Circuit Wiring Diagram. Normal to low High Compressor - low performance. Additional Possible Cause Components Associated With Inadequate Compressor Operation - Compressor drive belt - loose
- Compressor clutch - slipping
- Clutch coil open - shorted, or loose mounting
- Control assembly
- Clutch wiring circuit - high resistance, open or blown fuse
- Compressor operation interrupted by PCM
Additional Possible Cause Components Associated With a Damaged Compressor - Incorrect clutch air-gap
- Receiver/drier - plugged
- Refrigerant leaks
(1) Low pressure reading will be normal to high if pressure is taken at accumulator and if restriction is downstream of service access valve.
NOTE:
The following table is used to guide diagnosis of the refrigerant system if operating pressures are outside normal limits.