NO.23 A/C DOES NOT WORK SUFFICIENTLY[AJ (3.0L Duratec)]

id0103a7802900

23

A/C does not work sufficiently.

DESCRIPTION

•  A/C compressor magnetic clutch does not engage when A/C switch is turned on.

POSSIBLE CAUSE

•  Improper refrigerant charging amount

•  Open A/C magnetic clutch

•  Open circuit between A/C relay and A/C magnetic clutch

•  Poor ground of A/C magnetic clutch

•  Refrigerant pressure switch is stuck open.

•  A/C relay is stuck open.

•  Seized A/C compressor

•  Open circuit between A/C switch and PCM through both refrigerant pressure switch and A/C amplifier

Diagnostic procedure

STEP	INSPECTION	RESULTS	ACTION
1	• Connect the M-MDS to the DLC–2. • Turn the ignition switch to the ON position (Engine off). • Retrieve any DTCs. • Is “PASSED” displayed?	Yes	No DTC is displayed: • Go to the next step.
1		No	DTC is displayed: • Go to the appropriate DTC test.
2	• Disconnect the A/C compressor connector. • Start the engine and turn A/C switch on. • Is there correct voltage at terminal of A/C magnetic clutch connector? Specification Above 10.5 V	Yes	Inspect for ground condition of magnetic clutch on A/C compressor. • If the ground condition is normal, inspect for open circuit of magnetic clutch coil.
2		No	Go to the next step.
3	• Disconnect the refrigerant pressure switch connector. • Connect jumper wire between terminals B and C (high and low pressure side) of refrigerant pressure switch connector. • Turn the ignition switch to the ON position (Engine off). • Turn A/C switch on and set blower fan at any speed. • Does A/C work?	Yes	Inspect the refrigerant pressure switch operation. • If the switch is normal, go to the next step.
3		No	Inspect for the following: • A/C switch is stuck open. • Open circuit between refrigerant pressure switch and PCM terminal 41 • Open circuit of blower motor fan switch and resistor (if blower motor does not operate) • Inspect the evaporator temperature sensor and A/C amplifier.
4	• Remove the jumper wire from switch connector. • Reconnect connector to refrigerant pressure switch. • Start the engine and turn A/C switch on. • Does fan operate?	Yes	Inspect for the following: • A/C relay is stuck open. • Open circuit between A/C relay and PCM terminal 69
4		No	Inspect following and repair or replace if necessary: • Refrigerant charging amount • A/C compressor for being seized.
5	• Verify the test results. ― If normal, return to the diagnostic index to service any additional symptoms. ― If malfunction remains, inspect related Service Information and perform repair or diagnosis. • If vehicle is repaired, troubleshooting completed. • If vehicle is not repaired or additional diagnostic information is not available, replace the PCM.

23	A/C does not work sufficiently.
DESCRIPTION	• A/C compressor magnetic clutch does not engage when A/C switch is turned on.
POSSIBLE CAUSE	• Improper refrigerant charging amount • Open A/C magnetic clutch • Open circuit between A/C relay and A/C magnetic clutch • Poor ground of A/C magnetic clutch • Refrigerant pressure switch is stuck open. • A/C relay is stuck open. • Seized A/C compressor • Open circuit between A/C switch and PCM through both refrigerant pressure switch and A/C amplifier