NO.25 A/C DOES NOT WORK SUFFICIENTLY [MZR-CD 2.2]

id0103f3822300

25

A/C DOES NOT WORK SUFFICIENTLY

DESCRIPTION

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

POSSIBLE CAUSE

•  Improper refrigerant charge amount

•  Open A/C switch magnetic clutch

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

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

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

•  Open circuit in wiring harness between A/C relay and ignition switch (IG2) (vehicles without advanced keyless entry and push button start system)

•  Open circuit in wiring harness between A/C relay and IG2 relay (vehicles with advanced keyless entry and push button start system)

•  Poor ground of A/C magnetic clutch

•  Improper A/C magnetic clutch clearance

•  Refrigerant pressure switch is stuck open

•  Evaporator temperature sensor malfunction

•  Climate control unit malfunction (A/C switch malfunction or climate control unit does not determine A/C request or transmit the A/C request signal)

•  Instrument cluster malfunction (does not transmit A/C request signal to PCM)

•  Communication error between PCM and instrument cluster

•  Communication error between instrument cluster and climate control unit

•  A/C relay is stuck open

•  Improper A/C cut-off control

25	A/C DOES NOT WORK SUFFICIENTLY
DESCRIPTION	• A/C compressor magnetic clutch does not engage when the A/C switch is turned on.
POSSIBLE CAUSE	• Improper refrigerant charge amount • Open A/C switch magnetic clutch • Open circuit between A/C relay and A/C magnetic clutch • Open circuit in wiring harness between A/C relay and PCM • Open circuit in wiring harness between A/C relay and battery • Open circuit in wiring harness between A/C relay and ignition switch (IG2) (vehicles without advanced keyless entry and push button start system) • Open circuit in wiring harness between A/C relay and IG2 relay (vehicles with advanced keyless entry and push button start system) • Poor ground of A/C magnetic clutch • Improper A/C magnetic clutch clearance • Refrigerant pressure switch is stuck open • Evaporator temperature sensor malfunction • Climate control unit malfunction (A/C switch malfunction or climate control unit does not determine A/C request or transmit the A/C request signal) • Instrument cluster malfunction (does not transmit A/C request signal to PCM) • Communication error between PCM and instrument cluster • Communication error between instrument cluster and climate control unit • A/C relay is stuck open • Improper A/C cut-off control

Diagnostic Procedure

STEP	INSPECTION	RESULTS	ACTION
1	Connect the M-MDS to the DLC-2. Switch the ignition to ON (engine off). Retrieve PCM, instrument cluster, information display and climate control unit DTCs. Are there any DTCs displayed?	Yes	DTC is displayed: Go to appropriate DTC inspection. (See DTC TABLE [MZR-CD 2.2].) (See DTC TABLE [FULL-AUTO AIR CONDITIONER].) (See DTC TABLE [INFORMATION DISPLAY/MULTI INFORMATION DISPLAY].) (See DTC TABLE [INSTRUMENT CLUSTER].)
1		No	No DTC is displayed: Go to the next step.
2	Access PCM PID ACCS using the M-MDS. Start the engine and idle it. Turn the PID ACCS to ON from OFF using the M-MDS simulation function. Is the A/C magnetic clutch engaged?	Yes	Go to Step 10.
2		No	Go to the next step.
3	Access PCM PIDs COLP and AC_REQ. Monitor the COLP and AC_REQ PID while turning on and off the air conditioner by switching the control panel. Is the PID normal? (See PCM INSPECTION [MZR-CD 2.2].)	Yes	Go to Step 6.
3		No	Go to the next step.
4	Inspect refrigerant pressure switch. (See REFRIGERANT PRESSURE SWITCH INSPECTION [FULL-AUTO AIR CONDITIONER].) Is the refrigerant pressure switch normal?	Yes	Go to the next step.
4		No	Replace the refrigerant pressure switch. (See REFRIGERANT PRESSURE SWITCH REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
5	Inspect for following: • Refrigerant charging amount • A/C compressor seizure Are there items normal?	Yes	Go to Step 8.
5		No	Repair or replace malfunctioning part according to inspection result.
6	Access climate control unit PID EVAP_TEMP. Monitor the EVAP_TEMP PID while turning on and off the air conditioner by switching the control panel. Is the PID normal?	Yes	Go to Step 8.
6		No	Go to the next step.
7	Inspect the evaporator temperature sensor. (See EVAPORATOR TEMPERATURE SENSOR INSPECTION [FULL-AUTO AIR CONDITIONER].) Is the evaporator temperature sensor normal?	Yes	Inspect and repair for open or short circuit between evaporator temperature sensor and climate control unit.
7		No	Replace the evaporator temperature sensor. (See EVAPORATOR TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
8	Verify the information display indication of A/C system while turning on and off the air conditioner by switching the control panel. Does the information display indicate properly?	Yes	Replace the instrument cluster. (Instrument cluster does not receive the A/C request signal from climate control unit or transmit to PCM.) (See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
8		No	Replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (A/C switch malfunction or climate control unit does not determine A/C request or transmit it.)
9	Start the engine and idle it. Turn the PID ACCS to ON from OFF using the M-MDS simulation function. Measure the A/C compressor terminal and body ground. Is the voltage specified? Specification 10.5 V or more	Yes	Go to the next step.
9		No	Go to Step 12.
10	Inspect the A/C compressor magnetic clutch. (See MAGNETIC CLUTCH INSPECTION [FULL-AUTO AIR CONDITIONER].) Is the magnetic clutch normal?	Yes	Inspect and repair for open or short circuit between battery positive terminal and A/C compressor terminal A.
10		No	Replace the magnetic clutch. (See MAGNETIC CLUTCH DISASSEMBLY/ASSEMBLY [FULL-AUTO AIR CONDITIONER].)
11	Inspect the A/C relay. (See RELAY INSPECTION.) Is the A/C relay normal?	Yes	Go to the next step.
11		No	Replace the A/C relay.
12	Turn the ignition off. Disconnect the A/C replay and PCM connectors. Verify continuity between A/C relay and PCM terminal 1BX at wiring harness-side connector. Is there continuity?	Yes	Inspect for open in followings: • Between ignition switch (IG2) and A/C relay (vehicles without advanced keyless entry and push button start system) • Between IG2 relay and A/C relay (vehicles with advanced keyless entry and push button start system) • Between battery positive terminal and A/C relay • Between A/C relay and A/C magnetic clutch Repair or replace the malfunctioning part according to the inspection results.
12		No	Repair or replace for open circuit.
13	Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [MZR-CD 2.2].) • If the malfunction remains, inspect the related Service Information and perform repair or diagnosis. ― If the vehicle is repaired, troubleshooting completed. ― If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if later calibration is available. Retest.