NO.23 A/C DOES NOT WORK SUFFICIENTLY [MZR 1.5, MZR 1.6]

id0103e0802900

23

A/C DOES NOT WORK SUFFICIENTLY

DESCRIPTION

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

POSSIBLE CAUSE

•  Improper A/C magnetic clutch clearance

•  Refrigerant pressure sensor (full-auto air conditioner) or refrigerant pressure switch (manual air conditioner) is stuck open

•  Improper refrigerant charge amount

•  Evaporator temperature sensor malfunction

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

•  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)

•  Communication error between instrument cluster and climate control unit (for full-auto air conditioner)

•  Communication error between PCM and instrument cluster

•  Open or short to power supply circuit between instrument cluster terminal 2I and climate control unit terminal 2P (16-pin) (for manual air conditioner)

•  Poor ground of A/C magnetic clutch

•  Open A/C magnetic clutch

•  A/C relay stuck open

•  Improper A/C cut-off control

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

•  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)

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

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

•  PCM malfunction

23	A/C DOES NOT WORK SUFFICIENTLY
DESCRIPTION	• The A/C compressor magnetic clutch does not engage when the A/C is turned on.
POSSIBLE CAUSE	• Improper A/C magnetic clutch clearance • Refrigerant pressure sensor (full-auto air conditioner) or refrigerant pressure switch (manual air conditioner) is stuck open • Improper refrigerant charge amount • Evaporator temperature sensor malfunction • Instrument cluster malfunction (does not transmit A/C request signal to PCM) • 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) • Communication error between instrument cluster and climate control unit (for full-auto air conditioner) • Communication error between PCM and instrument cluster • Open or short to power supply circuit between instrument cluster terminal 2I and climate control unit terminal 2P (16-pin) (for manual air conditioner) • Poor ground of A/C magnetic clutch • Open A/C magnetic clutch • A/C relay stuck open • Improper A/C cut-off control • Open circuit in wiring harness between A/C relay and PCM • 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) • Open circuit in wiring harness between A/C relay and battery • Open circuit in wiring harness between A/C relay and A/C magnetic clutch • PCM malfunction

Diagnostic procedure

STEP	INSPECTION	ACTION
1	Retrieve the PCM, instrument cluster, multi information display and climate control unit (for full-auto air conditioner) DTCs. (See ON-BOARD DIAGNOSTIC TEST [MZR 1.5, MZR 1.6].) (See DTC INSPECTION [INSTRUMENT CLUSTER].) (See DTC INSPECTION [INFORMATION DISPLAY/MULTI INFORMATION DISPLAY].) (See DTC DISPLAY [FULL-AUTO AIR CONDITIONER].) Are any DTCs present?	Yes	Go to the appropriate DTC inspection. (See DTC TABLE [MZR 1.5, MZR 1.6].) (See DTC TABLE [INSTRUMENT CLUSTER].) (See DTC TABLE [INFORMATION DISPLAY/MULTI INFORMATION DISPLAY].) (See DTC TABLE [FULL-AUTO AIR CONDITIONER].)
1		No	Go to the next step.
2	Access the ACCS PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [MZR 1.5, MZR 1.6].) 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 13.
2		No	Go to the next step.
3	Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [MZR 1.5, MZR 1.6].) • COLP • AC_REQ Monitor the each PID while turning on and off the air conditioner by switching the control panel. Are all PIDs normal? (See PCM INSPECTION [MZR 1.5, MZR 1.6].)	Yes	Full-auto air conditioner: • Go to Step 6. Manual air conditioner: • Go to Step 7.
3		No	Go to the next step.
4	Inspect the refrigerant pressure sensor (full-auto air conditioner) or refrigerant pressure switch (manual air conditioner). (See REFRIGERANT PRESSURE SENSOR INSPECTION [FULL-AUTO AIR CONDITIONER].) (See REFRIGERANT PRESSURE SWITCH INSPECTION [MANUAL AIR CONDITIONER].) Is the refrigerant pressure switch normal?	Yes	Go to the next step.
4		No	Replace the refrigerant pressure sensor (full-auto air conditioner) or refrigerant pressure switch (manual air conditioner). (See REFRIGERANT PRESSURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See REFRIGERANT PRESSURE SWITCH REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
5	Inspect for following: • Refrigerant charging amount • A/C compressor seizure Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results.
5		No	Full-auto air conditioner: • Go to Step 9. Manual air conditioner: • Go to Step 11.
6	Connect the M-MDS to the DLC-2. Access the climate control unit PID EVAP_TEMP. (See PID/DATA MONITOR DISPLAY [FULL-AUTO AIR CONDITIONER].) Monitor the EVAP_TEMP PID while turning on and off the air conditioner by switching the control panel. Is the PID value normal? (See PID/DATA MONITOR TABLE [FULL-AUTO AIR CONDITIONER].)	Yes	Go to Step 9.
6		No	Go to Step 8.
7	Remove the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) Reconnect the climate control unit connector with it removed. Measure the voltage between climate control unit terminal 1C (wiring harness-side) and body ground. Is the voltage within the specified? (See CLIMATE CONTROL UNIT INSPECTION [MANUAL AIR CONDITIONER].)	Yes	Go to Step 11.
7		No	Go to the next step.
8	Inspect the evaporator temperature sensor. (See EVAPORATOR TEMPERATURE SENSOR INSPECTION [FULL-AUTO AIR CONDITIONER].) (See EVAPORATOR TEMPERATURE SENSOR INSPECTION [MANUAL AIR CONDITIONER].) Is there any malfunction?	Yes	Replace the evaporator temperature sensor. (See EVAPORATOR TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See EVAPORATOR TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
8		No	Inspect and repair for open or short circuit between evaporator temperature sensor and climate control unit.
9	Verify the multi information display indication of A/C system while turning on and off the air conditioner by switching the control panel. Does the multi 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.)
9		No	Go to the next step.
10	Inspect the multi information display. (See MULTI INFORMATION DISPLAY INSPECTION.) Is the multi information display normal?	Yes	Replace the climate control unit. (A/C switch malfunction or climate control unit does not determine A/C request or transmit it.) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
10		No	Repair or replace the malfunctioning part according to the inspection results.
11	Remove the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) Reconnect the climate control unit connector with it removed. Measure the voltage between climate control unit terminal 2P (wiring harness-side) and body ground while turning on and off air conditioner by switching the control panel. Is the voltage change in specified according to the control panel switching? (See CLIMATE CONTROL UNIT INSPECTION [MANUAL AIR CONDITIONER].)	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.)
11		No	Go to the next step.
12	Inspect for open or short to power supply in wiring harness between climate control unit terminal 2P (16-pin) and instrument cluster terminal 2I. Is there any malfunction?	Yes	Repair or replace the suspected wiring harness.
12		No	Replace the climate control unit. (A/C switch malfunction or climate control unit does not determine A/C request or transmit to the A/C request signal.) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
13	Disconnect the A/C compressor connector. Start the engine and idle it. Turn the PID ACCS to On from Off using the M-MDS simulation function. Measure the voltage between magnetic clutch terminal A and body ground. Is the voltage 10.5 V or more?	Yes	Go to the next step.
13		No	Go to Step 15.
14	Inspect the A/C compressor magnetic clutch. (See MAGNETIC CLUTCH INSPECTION [FULL-AUTO AIR CONDITIONER].) (See MAGNETIC CLUTCH INSPECTION [MANUAL 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.
14		No	Replace the magnetic clutch.
15	Inspect the A/C relay. (See RELAY INSPECTION.) Is the A/C relay normal?	Yes	Go to the next step.
15		No	Replace the A/C relay.
16	Switch the ignition to off. Remove the A/C relay. Disconnect the PCM connector. Inspect for continuity between A/C relay terminal E (wiring harness-side) and PCM terminal 1AN (wiring harness-side). Is there continuity?	Yes	Inspect the following: • 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.
16		No	Repair or replace the suspected wiring harness.
17	Verify the test results. • If normal, return to diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [MZR 1.5, MZR 1.6].) • 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 [MZR 1.5, MZR 1.6].)