A048

Diagnostic Chart:

CIRCUIT DESCRIPTION
In the process of controlling the compressor clutch, the ACP monitors certain system inputs for an indication of low refrigerant charge, The ACP monitors the normally closed low refrigerant pressure switch at pin "C3." The status of the low pressure switch is checked prior to compressor engagement. If the return voltage to the ACP indicates the switch is open, the compressor will not be allowed to engage and a Code A048 will be set in diagnostics. Additionally, the ECC will switch to ECON mode and the A/C Low Refrigerant message will be displayed.

FAILURE CONDITIONS
A048 - Very Low Refrigerant Pressure Condition will set if the low refrigerant pressure switch remains open for several minutes.

ACTION TAKEN
A048 - Display "VERY LOW REFRIGERANT - A/C COMPRESSOR OFF" message on DIC. Disable compressor until diagnostic codes are cleared.

NOTES ON FAULT TREE
1. Checks current state of low pressure switch.
2. Checks circuits to low pressure switch.
3. Checks refrigerant system pressure.
4. Checks for restriction in refrigerant system.
5. Checks for intermittent short/open.