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Diagnostic procedure

WARNING: This page is about a different variant/trim than selected.
DIAGNOSTIC PROCEDURE CHART

STEP INSPECTION RESULTS ACTION
1 VERIFY PCM AND CLIMATE CONTROL UNIT DTC  Yes Go to the appropriate DTC inspection.
(See DTC TABLE .)
(See DTC TABLE .)
(See DTC TABLE [ARAB GULF COOPERATION COUNCIL] .)
No Go to the next step.
2 DETERMINE IF MALFUNCTION CAUSE IS A/C REQUEST SIGNAL OR MAGNET CLUTCH DRIVE SIGNAL 
  • Access the PCM PID ACCS using the M-MDS.

    (See ON-BOARD DIAGNOSTIC TEST .)

  • Start the engine and idle it.
  • Turn the PID ACCS to ON from OFF using the M-MDS simulation function.
  • Is the magnetic clutch engaged?
 Yes Go to the next step.
No Go to Step 13.
3 DETERMINE IF MALFUNCTION CAUSE IS EVAPORATOR TEMPERATURE SIGNAL OR OTHER 
  • Access the PCM PID AC REQ using the M-MDS.

    (See ON-BOARD DIAGNOSTIC TEST .)

  • Start the engine and idle it.
  • Monitor the PID AC_REQ while turning on and off the air conditioner by switching the control panel.
  • Does the PID change according to air control panel switching?

(See PCM INSPECTION .)		 Yes Go to the next step.
No Full-auto air conditioner:
  • Go to Step 6.

Manual air conditioner:
  • Go to Step 7.
4 DETERMINE IF MALFUNCTION CAUSE IS REFRIGERANT PRESSURE SENSOR OR OTHER 
  • Access the PCM PID COLP using the M-MDS.

    (See ON-BOARD DIAGNOSTIC TEST .)

  • Monitor the COLP PID while turning on and off the air conditioner by switching the control panel.
  • Is the PID value normal?

(See PCM INSPECTION .)		 Yes Go to Step 13.
No Go to the next step.
5 INSPECT REFRIGERANT PRESSURE SENSOR  Yes Inspect for following:
  • Refrigerant charging amount
  • Magnetic clutch for seizure

Repair or replace the malfunctioning part according to the inspection results.
No Inspect the following:
  • A/C switch is stuck open.
  • pen circuit in wiring harness between the refrigerant pressure sensor and PCM terminal 1J
  • Open circuit in wiring harness between front blower motor and resistor (If the front blower motor does not operate.)
  • Evaporator temperature sensor and climate control unit

Repair or replace the malfunctioning part according to the inspection results.
6 DETERMINE IF MALFUNCTION CAUSE IS EVAPORATOR TEMPERATURE SENSOR OR OTHER (FULL-AUTO AIR CONDITIONER) 
  • Access the climate control unit PID EVAP TEMP using the M-MDS. (See PID/DATA MONITOR DISPLAY .)
  • Monitor the EVAP_TEMP PID white turning on and off the air conditioner by switching the control panel.
  • Is the PID value normal?
 Yes Go to Step 9.
No Go to Step 8.
7 DETERMINE IF MALFUNCTION CAUSE IS EVAPORATOR TEMPERATURE SENSOR OR OTHER (MANUAL AIR CONDITIONER) 
(See CLIMATE CONTROL UNIT INSPECTION [MANUAL AIR CONDITIONER] .)		 Yes Go to Step 11.
No Go to the next step.
8 INSPECT EVAPORATOR TEMPERATURE SENSOR  Yes Inspect for open or short circuit between evaporator temperature sensor and climate control unit. Repair or replace suspected wiring harness and connector.
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
No Replace the evaporator temperature sensor.
(See EVAPORATOR TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
(See EVAPORATOR TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
9 DETERMINE IF MALFUNCTION CAUSE IS INSTRUMENT CLUSTER OR OTHER (FULL-AUTO AIR CONDITIONER) 
  • 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 A/C request signal from climate control unit or transmit it to PCM.)
(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION .)
No Go to the next step.
10 DETERMINE IF MALFUNCTION CAUSE IS CLIMATE CONTROL UNIT OR OTHER (FULL-AUTO AIR CONDITIONER)  Yes Repair or replace the malfunctioning part according to the inspection results.
No Replace the climate control unit. (A/C switch malfunction or climate control unit does not determine A/C request or transmit the A/C request signal.) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
11 DETERMINE IF MALFUNCTION CAUSE IS INSTRUMENT CLUSTER OR OTHER (MANUAL AIR CONDITIONER) 
  • Remove the climate control unit.

    (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)

  • Reconnect the climate control unit connector.
  • Start the engine and idle it.
  • Measure the voltage at the climate control unit terminal 1L while turning on and off the air conditioner by switching the control panel.
  • Is the voltage change in specified according to air control panel switching?

(See CLIMATE CONTROL UNIT INSPECTION [MANUAL AIR CONDITIONER] .)
Specification 
  • Turn on the A/C: Below 1.0 V 
  • Turn off the A/C: Approx. 5 V 
 Yes Replace the instrument cluster. (Instrument cluster does not receive A/C request signal from climate control unit or transmit it to PCM.)
(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION .)
No Go to the next step.
12 DETERMINE IF MALFUNCTION CAUSE IS A/C REQUEST SIGNAL RELATED WIRING HARNESS OR CLIMATE CONTROL UNIT (MANUAL AIR CONDITIONER) 
  • Inspect for open or short circuit between climate control unit terminal 1L and instrument cluster terminal 1A.
  • Is there any open or short circuit detected?
 Yes Repair or replace suspected wiring harness and connector.
No Replace the climate control unit. (A/C switch malfunction or climate control unit does not determine A/C request or transmit the A/C request signal.) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
13 DETERMINE IF MALFUNCTION CAUSE IS A/C CONTROL SIGNAL OR MAGNETIC CLUTCH 
  • 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 specified?

Specification 
  • 10.5 V or more 
 Yes Go to the next step.
No Go to Step 15.
14 INSPECT MAGNETIC CLUTCH GROUND CIRCUIT FOR OPEN CIRCUIT 
  • Verify continuity between magnetic clutch terminal A and body ground.
  • Is there any continuity?
 Yes Replace the A/C compressor.
(See A/C COMPRESSOR REMOVAL/INSTALLATION .)
No Repair or replace suspected wiring harness and/or poor contact ground points.
15 INSPECT A/C RELAY  Yes Go to the next step.
No Replace the A/C relay.
16 INSPECT A/C RELAY CONTROL CIRCUIT FOR OPEN CIRCUIT 
  • Switch the ignition to off.
  • Disconnect the A/C relay and PCM connectors.
  • Verify continuity between A/C relay and PCM terminal 1I (wiring harness-side).
  • Is there any continuity?
 Yes Inspect for open circuit in followings:
  • Between ignition switch (IG2)(1)/IG2 relay(2) and A/C relay
  • Between battery positive terminal and A/C relay
  • Between A/C relay and magnetic clutch

Repair or replace suspected wiring harness and connector.
No Repair or replace suspected wiring harness and connector.
17
  • Verify test results.
  • If normal, return to diagnostic index to service any additional symptoms.

    (See SYMPTOM DIAGNOSTIC INDEX .)

  • If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
  • If vehicle is repaired, troubleshooting completed.
  • If vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.
(1) Without advanced keyless entry and push button start system
(2) With advanced keyless entry and push button start system
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