NO.23 A/C DOES NOT WORK SUFFICIENTLY [L8, LF]

id0103a0802900

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

•  Poor ground of A/C magnetic clutch

•  Open circuit A/C magnetic clutch

•  Refrigerant pressure switch is stuck open

•  A/C relay is stuck open

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

•  Open circuit in wiring harness between A/C relay and A/C magnetic clutch

•  Seized A/C compressor

•  Improper refrigerant charging amount

•  PCM malfunction

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	• Poor ground of A/C magnetic clutch • Open circuit A/C magnetic clutch • Refrigerant pressure switch is stuck open • A/C relay is stuck open • Open circuit in wiring harness between A/C switch and PCM through both refrigerant pressure switch and A/C amplifier • Open circuit in wiring harness between A/C relay and A/C magnetic clutch • Seized A/C compressor • Improper refrigerant charging amount • PCM malfunction

Diagnostic procedure

STEP	INSPECTION	RESULTS	ACTION
1	Connect the M-MDS to the DLC-2. Perform the KOEO/KOER self test and the DTC Reading Procedure. (See KOEO/KOER SELF TEST [L8, LF].) (See ON-BOARD DIAGNOSTIC TEST [L8, LF].) Are any DTCs present?	Yes	Go to the appropriate DTC inspection. (See DTC TABLE [L8, LF].)
1		No	Go to the next step.
2	Disconnect the A/C compressor connector. Start the engine and turn the A/C switch on. Is there correct voltage A/C compressor magnetic clutch terminal? Specification More than 10.5 V	Yes	Inspect for ground condition of magnetic clutch on A/C compressor. Repair or replace the malfunctioning part according to the inspection results. If ground condition is normal: • Inspect for open circuit magnetic clutch coil. • Repair or replace the malfunctioning part according to the inspection results.
2		No	Go to the next step.
3	Disconnect the refrigerant pressure switch connector. Connect the jumper wire between A/C high-pressure switch terminal. Connect jumper wires between refrigerant pressure switch terminal. Connect the M-MDS to the DLC-2. Perform the PID/DATA Monitor and Record Procedure and access the AC_REQ PID: (See ON-BOARD DIAGNOSTIC TEST [L8, LF].) Turn the ignition switch to the ON position. Turn the A/C switch on and set blower fan at any speed. Does the AC_REQ PID read On?	Yes	Inspect the refrigerant pressure switch. (See REFRIGERANT PRESSURE SWITCH INSPECTION [MANUAL AIR CONDITIONER].) (See REFRIGERANT PRESSURE SWITCH INSPECTION [FULL-AUTO AIR CONDITIONER].) Repair or replace the malfunctioning part according to the inspection results. If the refrigerant pressure switch is normal: • Go to the next step.
3		No	Inspect the following: • A/C switch is stuck open • Open circuit in wiring harness between refrigerant pressure switch and PCM terminal 1AU • Open circuit of blower motor fan switch and resistor (if blower motor does not operate) • Evaporator temperature sensor and A/C amplifier Repair or replace the malfunctioning part according to the inspection results.
4	Remove the jumper wire from the refrigerant pressure switch connector. Reconnect the refrigerant pressure switch connector. Start the engine and turn the A/C switch on. Does the fan operate?	Yes	Inspect for stuck open A/C relay. Replace the A/C relay, if necessary.
4		No	Inspect the following: • A/C compressor for being seized • Refrigerant charging amount Repair or replace the malfunctioning part according to the inspection results.
5	Verify test results. • If normal, return to diagnostic index to service any additional symptoms. (See ENGINE SYMPTOM TROUBLESHOOTING [L8, LF].) • If malfunction remains, inspect related Service information perform repair or diagnosis. ― If vehicle repaired, troubleshooting completed. ― If vehicle not repaired or additional diagnostic information not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [L8, LF].)