INSPECTION
Before performing the diagnosis, check the following items which may cause problems in the A/C system.
A/C CONTROL PANEL SELF-DIAGNOSIS
| Step | Check | Yes | No |
|---|---|---|---|
| 1 SELECT SELF-DIAGNOSIS MODE IN THE CONTROL PANEL . Set the air flow control dial and fan speed control dial to the AUTO position. Start the engine with the A/C switch and the FRESH/RECIRC switch pressed. | Does the self-diagnosis mode operate? | Go to step 2 . | Refer to A/C OR SELF-DIAGNOSIS SYSTEMS DO NOT OPERATE , Diagnostics for A/C System Malfunction . |
| 2 CHECK THE LIGHTING OF THE LED . Make sure that all switch LEDs on the control panel illuminate. | Do all LEDs blink eight times? | Go to step 3 . | Replace the control panel. |
| 3 CHECK SENSOR MALFUNCTION . Set the air flow control dial and fan speed control dial to the AUTO position. If the system has trouble for each sensor, the FRESH/RECIRC switch LED blinks or is turned off. If the system has no trouble, the FRESH/RECIRC switch LED illuminates. | Does the FRESH/RECIRC switch LED illuminate? | Go to step 5 . | Go to step 4 . |
| 4 CONFIRM MALFUNCTIONING SENSOR . Set the air flow control dial to the AUTO position. Turn the fan speed control dial to each mode position, and check each switch LED illumination according to the sensor check table. Refer to SENSOR CHECK TABLE , OPERATION, Diagnostic Chart for Self-diagnosis . | When the fan dial is set to the individual mode positions, does the FRESH/RECIRC switch LED turn off? | Go to step 5 . | Repair the defective sensor. Refer to DIAGNOSTIC PROCEDURE FOR SENSORS . |
| 5 CHECK AIR MIX DOOR AND MODE DOOR POSITION SIGNALS . Set the airflow control dial to the FACE position. Turn the fan dial to AUTO. If the system has trouble for air mix door signal and mode door position signal, the FRESH/RECIRC switch LED is turned off or blinks. If the system has no trouble, the FRESH/RECIRC switch LED illuminates. | Does the FRESH/RECIRC switch LED illuminate? | Go to step 6 . | Check the mode door actuator circuit. Refer to MODE DOOR ACTUATOR , Diagnostic Procedure for Actuators . |
| 6 CHECK AIR MIX DOOR AND MODE DOOR POSITION DRIVE SIGNALS . Set the air flow control dial to the FACE position. Set the fan speed control dial to each position, and check the lighting conditions of each LED. Refer to A/C CONTROL PANEL SELF-DIAGNOSIS , OPERATION, Diagnostic Chart for Self-diagnosis . | Does the lighting conditions of the LED match the drive signal list? | Go to step 7 . | Check the air mix door actuator circuit. Refer to AIR MIX DOOR ACTUATOR , Diagnostic Procedure for Actuator . |
| 7 CHECK AIR MIX DOOR AND MODE DOOR POSITION DRIVE SIGNALS . Press the A/C switch. Set the fan speed control dial to each position, and check the lighting conditions of each LED. Refer to A/C CONTROL PANEL SELF-DIAGNOSIS , OPERATION, Diagnostic Chart for Self-diagnosis . | Does the lighting conditions of the LED match the drive signal list? | Go to step 8 . | Check the mode door actuator circuit. Refer to MODE DOOR ACTUATOR , Diagnostic Procedure for Actuate . |
| 8 CHECK OPERATION OF EACH ACTUATOR, BLOWER FAN AND COMPRESSOR CLUTCH . Set the air flow control dial to the B/L position. Set the fan speed control dial to AUTO - 7th position, and select the operating mode. Check the operation of each mode according to operating mode table. Refer to A/C CONTROL PANEL SELF-DIAGNOSIS , OPERATION, Diagnostic Chart for Self-diagnosis . FRESH/RECIRC door Air flow control door Air mix door Blower fan A/C compressor | Does the operation of each mode match to operating mode table? | Turn the fan speed control dial to OFF or turn the ignition switch to OFF, to complete the self diagnosis. | Repair the malfunctioning part in accordance with each diagnostic chart. |
A/C CONTROL PANEL SELF-DIAGNOSIS CHART
TROUBLE SYMPTOM
- Set temperature is not indicated on the display, switch LEDs are faulty and switches do not operate.
- Self-diagnosis system does not operate.
Scheme 41
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK FUSE . Turn the ignition switch to OFF. Remove the fuse No. 7 from fuse & relay box. Check the condition of fuse. | Is the fuse blown out? | Replace the fuse. | Go to step 2 . |
| 2 CHECK FUSE . Turn the ignition switch to OFF. Remove the fuse No. 22 and No. 31 from fuse & relay box. Check the condition of fuse. | Is the fuse blown out? | Replace the fuse. | Go to step 3 . |
| 3 CHECK A/C CONTROL UNIT POWER CIRCUIT . Remove the A/C control panel. Disconnect the A/C control panel harness connector. Measure the voltage between A/C control panel harness connector terminal and chassis ground after turning the ignition switch to ACC. Connector & terminal (i88) No. 15 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 4 . | Check for open or short circuit in the harness between A/C control panel and fuse. |
| 4 CHECK A/C CONTROL UNIT POWER CIRCUIT . Measure the voltage between A/C control panel harness connector terminal and chassis ground after turning the ignition switch to ON. Connector & terminal (i88) No. 32 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 5 . | Check for open or short circuit in the harness between A/C control panel and fuse. |
| 5 CHECK A/C CONTROL PANEL GROUND POWER CIRCUIT . Measure the resistance of harness between A/C control panel and chassis ground after turning the ignition switch to OFF. Connector & terminal (i88) No. 34 - Chassis ground | Is the resistance less than 1 ohms? | Go to step 6 . | Repair the harness for ground line. |
| 6 CHECK POOR CONTACT . Check poor contact of auto A/C control module connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
- Blower motor does not rotate.
- Blower motor does not change speeds.
Scheme 42
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK FUSE . Remove fuse No. 22,27 and 28 from the fuse & relay box. Check the condition of fuse. | Is any fuse blown out? | Replace the fuse. | Go to step 2 . |
| 2 CHECK BLOWER MOTOR RELAY POWER SUPPLY . Turn the ignition switch to OFF. Remove the blower motor relay. Turn the ignition switch to ON. Use a tester to measure the voltage between the blower motor relay connector and chassis ground. Connector & terminal (B386) No. 2 - Chassis ground | Is the voltage 10 V or more? | Go to step 3 . | Repair the open circuit of blower motor power supply line harness. |
| 3 CHECK BLOWER MOTOR RELAY POWER SUPPLY . Turn the ignition switch to ON. Turn the blower switch to ON. Use a tester to measure the voltage between the blower motor relay connectors. Connector & terminal (B386) No. 2 - No. 4 | Is the voltage 10 V or more? | Go to step 5 . | Go to step 4 . |
| 4 CHECK HARNESS . Turn the ignition switch to OFF. Disconnect the auto A/C control module connector (i88). Use a tester to measure the resistance between harness terminals. Connector & terminal (B386) No. 4 - (i88) No. 9 | Is the resistance less than 1 Q.? | Go to step 5 . | Repair or replace the open circuit of the harness. |
| 5 CHECK BLOWER MOTOR RELAY . Turn the ignition switch to OFF. Remove the blower motor relay. Connect the battery terminal to the blower motor relay. No. 2 (+) - No. 4 (-) Measure the resistance between terminals. Terminals No. 1 - No. 5 | Is the resistance less than 1 ohms? | Go to step 6 . | Replace the blower motor relay. |
| 6 CHECK BLOWER MOTOR POWER SUPPLY . Turn the ignition switch to OFF. Install the blower motor relay. Disconnect the blower motor connector. Turn the ignition switch to ON. Turn the blower switch to ON. Use a tester to measure the voltage between the blower motor connector and chassis ground. Connector & terminal (B87) No. 2 - Chassis ground | Is the voltage 10 V or more? | Go to step 7 . | Repair or replace the harness between the blower motor relay and the blower motor. |
| 7 CHECK BLOWER MOTOR . Disconnect the connector from the blower motor. Connect the battery positive terminal to terminal No. 2 of blower motor connector, and negative terminal to terminal No. 1. Make sure the blower motor runs. | Does the blower motor run? | Go to step 8 . | Replace the blower motor. |
| 8 CHECK HARNESS . Turn the ignition switch to OFF. Disconnect the power transistor connector. Disconnect the auto A/C control module connector. Use a tester to measure the resistance between harness terminals. Connector & terminal (B57) No. 1 - Chassis ground: (B57) No. 2 - (188) No. 40: (B57) No. 3 - (B87) No. 1: (B57) No. 4 - (B87) No. 2: (B57) No. 4 - (B386) No. 5 | Is the resistance less than 1 ohms? | Go to step 9 . | Repair or replace the harness. |
| 9 CHECK FAN CONTROL SIGNAL . Turn the ignition switch to OFF. Connect the blower motor and auto A/C control module. Turn the ignition switch to ON. Set the fan dial to 1st - 7th. Use a tester to measure the voltage between the power transistor connector and chassis ground. Connector & terminal (B57) No. 2 (+) - Chassis ground (-) | Is approx. 10V detected in 1st, and 1 V at 7th? | Replace the power transistor. Refer to REMOVAL , Power Transistor (Auto A/C Model) . | Go to step 10 . |
| 10 CHECK POOR CONTACT . Check poor contact of auto A/C control module connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
- The blower turns even though the blower switch is not turned ON.
- The blower motor continues to turn at high speed. (Cannot be adjusted).
- Compartment temperature does not change. (Cold air does not come out)
- The A/C system does not respond. (Response is extremely slow)
Scheme 43
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK FUSE . Turn the ignition switch to OFF. Remove the fuse No. 22 from fuse & relay box. Check the condition of fuse. | Is the fuse blown out? | Replace the fuse. | Go to step 2 . |
| 2 CHECK SIGNAL TO A/C RELAY AND AUTO A/C CONTROL MODULE . Disconnect the A/C relay and auto A/C control module harness connector. Turn the ignition switch to ON. Measure the voltage between A/C relay connector terminal and chassis ground. Measure the voltage between auto A/C control module harness connector terminal and chassis ground. Connector & terminal (F27) No. 17 (+) - Chassis ground (-): (i88) No. 11 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 5 . | Go to step 3 . |
| 3 CHECK POWER SUPPLY FOR PRESSURE SWITCH . Turn the ignition switch to OFF. Disconnect the pressure switch harness connector. Turn the ignition switch to ON. Measure the voltage between pressure switch harness connector terminal and chassis ground. Connector & terminal (B10) No. 2 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 4 . | Check for open or short circuit in the harness between fuse and pressure switch. |
| 4 CHECK HARNESS BETWEEN PRESSURE SWITCH AND A/C RELAY, AUTO A/C CONTROL MODULE . Turn the ignition switch to OFF. Measure the resistance of harness between pressure switch connector and A/C relay connector. Measure the resistance of harness between pressure switch connector and auto A/C control module connector. Connector & terminal (B10) No. 2 - (F27) No. 17: (B10) No. 2 - (i88) No. 11 | Is the resistance less than 1 ohms? | Check the pressure switch. Refer to INSPECTION , Pressure Switch (Triple Pressure Switch) . | Repair the harness. |
| 5 CHECK POWER SUPPLY FOR A/C RELAY . Measure the voltage between A/C relay connector terminal and chassis ground. Connector & terminal (F27) No. 14 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 6 . | Check open or short circuit of harness between fuse and A/C relay. |
| 6 CHECK A/C RELAY . Check the A/C relay. Refer to INSPECTION , Relay and Fuse . | Is there a malfunction in the A/C relay? | Go to step 7 . | Replace the A/C relay. |
| 7 CHECK A/C ON SIGNAL . Turn the ignition switch to OFF. Connect the A/C relay and all disconnected connectors. Start the engine and turn the A/C switch to ON. Turn the temperature control dial at maximum cool position. Measure the voltage between auto A/C control module harness connector terminal and chassis ground. Connector & terminal (i88) No. 36 (+) - Chassis ground (-) | Is the voltage 5.5 V or more? | Go to step 9 . | Go to step 8 . |
| 8 CHECK HARNESS BETWEEN AUTO A/C CONTROL MODULE AND ECM . Turn the ignition switch to OFF. Disconnect the harness connector of auto A/C control module and ECM. Measure the resistance of harness between auto A/C control module connector and ECM connector. Connector & terminal (i88) No. 36 - (B136) No. 24 | Is the resistance less than 1 ohms? | Replace the auto A/C control module. | Repair the harness. |
| 9 CHECK MAGNET CLUTCH ON SIGNAL . Stop the engine and turn the A/C switch to OFF. Turn the ignition switch to ON. Measure the voltage between ECM connector terminal and chassis ground. Connector & terminal (B136) No. 9 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 10 . | Check for open or short circuit in the harness between A/C relay and ECM. |
| 10 CHECK MAGNET CLUTCH ON SIGNAL . Start the engine and turn the A/C switch to ON. Turn the temperature control dial at maximum cool position. Measure the voltage between ECM connector terminal and chassis ground. Connector & terminal (B136) No. 9 (+) - Chassis ground (-) | Is the voltage 0 V? | Go to step 11 . | Replace the ECM. |
| 11 CHECK POWER SUPPLY FOR MAGNET CLUTCH . Stop the engine and turn the A/C switch to OFF. Disconnect the harness connector of magnet clutch. Start the engine and turn the A/C switch to ON. Turn the temperature control dial at maximum cool position. Measure the voltage between magnet clutch harness connector terminal and chassis ground. Connector & terminal (F24) No. 1 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Inspect the compressor. Refer to INSPECTION , Compressor . | Check for open or short circuit in the harness between A/C relay and magnet clutch. |
DIAGNOSIS PROCEDURE CHART
FRESH/RECIRC mode is not changed.
Scheme 44
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK POWER SUPPLY FOR INTAKE DOOR ACTUATOR . Turn the ignition switch to OFF. Disconnect the intake door actuator connector. Turn the ignition switch to ON. Measure the voltage between intake door actuator connector and chassis ground. Connector & terminal (B163) No. 1 (+) - Chassis ground (-) | Is the voltage 7 V (at normal temperature)? | Go to step 2 . | Check for open or short circuit in the harness between intake door actuator and fuse. |
| 2 CHECK HARNESS BETWEEN AUTO A/C CONTROL MODULE AND INTAKE DOOR ACTUATOR . Turn the ignition switch to OFF. Disconnect the auto A/C control module connector. Measure the resistance between intake door actuator connector and auto A/C control module connector. Connector & terminal (i88) No. 8 - (B163) No. 6: (i88) No. 7 - (B163) No. 5: (i88) No. 6 - (B163) No. 4 | Is the resistance less than 1 ohms? | Go to step 3 . | Repair the harness between auto A/C control module and intake door actuator. |
| 3 CHECK OPERATION OF INTAKE DOOR ACTUATOR . Connect the intake door actuator connector. Ground the auto A/C control module connector with a suitable wire. Turn the ignition switch to ON, and check the operation of intake door actuator. Connector & terminal (B163) No. 4 - Chassis ground | Does the actuator move to the FRESH side? | Go to step 4 . | Replace the intake door actuator. |
| 4 CHECK OPERATION OF INTAKE DOOR ACTUATOR . Turn the ignition switch to OFF. Ground the auto A/C control module connector with a suitable wire. Turn the ignition switch to ON, and check the operation of intake door actuator. Connector & terminal: (B163) No. 5 - Chassis ground | Does the actuator move to the RECIRC side? | Replace the auto A/C control module. | Replace the intake door actuator. |
DIAGNOSIS PROCEDURE CHART
Air flow outlet is not changed.
Scheme 45
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK POWER SUPPLY FOR MODE DOOR ACTUATOR . Turn the ignition switch to OFF. Disconnect the mode door actuator connector. Turn the ignition switch to ON. Measure the voltage between the mode door actuator connector terminal and chassis ground. Connector & terminal (B77) No. 3 (+) - Chassis ground (-) | Is the voltage approx. 10 V or more? | Go to step 2 . | Repair the DC power supply circuit. |
| 2 CHECK MODE DOOR ACTUATOR . Disconnect the mode door actuator connector. Use a tester to measure the resistance between mode door actuator terminals. Connector & terminal (B77) No. 3 - No. 1: (B77) No. 3 - No. 2: (B77) No. 3 - No. 5: (B77) No. 3 - No. 6 | Is the resistance between 80 - 100 ohms? | Go to step 3 . | Replace the mode door actuator. |
| 3 CHECK HARNESS BETWEEN AUTO A/C CONTROL MODULE AND MODE DOOR ACTUATOR . Turn the A/C and ignition switch to OFF. Disconnect the auto A/C control module connector. Measure the resistance between auto A/C control module and mode door actuator connector. Connector & terminal (B77) No. 1 - (i88) No. 4: (B77) No. 2 - (i88) No. 3: (B77) No. 5 - (i88) No. 2: (B77) No. 6 - (i88) No. 1 | Is the resistance less than 1 ohms? | Go to step 4 . | Repair the harness between auto A/C control module and mode door actuator. |
| 4 CHECK POOR CONTACT . Check poor contact of auto A/C control module and connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
Outlet air temperature does not change.
Scheme 46
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK AIR MIX DOOR ACTUATOR POWER SUPPLY . Turn the ignition switch to OFF. Disconnect the air mix door actuator connector. Turn the ignition switch to ON. Measure the voltage between the air mix door actuator connector terminal and chassis ground. Connector & terminal (B239) No. 3 (+) - Chassis ground (-) | Is the voltage approx. 10 V or more? | Go to step 2 . | Repair the DC power supply circuit. |
| 2 CHECK AIR MIX DOOR ACTUATOR . Disconnect the air mix door actuator connector. Use a tester to measure the resistance between the air mix actuator terminals. Connector & terminal (B239) No. 3 - No. 1: (B239) No. 3 - No. 2: (B239) No. 3 - No. 5: (B239) No. 3 - No. 6 | Is the resistance between 80- 100ohms? | Go to step 3 . | Replace the air mix door actuator. |
| 3 CHECK HARNESS BETWEEN AUTO A/C CONTROL MODULE AND AIR MIX DOOR ACTUATOR . Turn the A/C and ignition switch to OFF. Disconnect the auto A/C control module connector. Measure the resistance between auto A/C control module and air mix door actuator connector. Connector & terminal (B239) No. 1 - (i88) No. 28: (B239) No. 2 - (i88) No. 27: (B239) No. 5 - (i88) No. 26: (B239) No. 6 - (i88) No. 25 | Is the resistance less than 1 ohms? | Go to step 4 . | Repair the harness between auto A/C control module and air mix door actuator. |
| 4 CHECK POOR CONTACT . Check poor contact of auto A/C control module and connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
- Fan speed is not switched when the fan speed control dial is in AUTO position.
- Failure related to the ambient sensor is indicated in self-diagnosis.
Scheme 47
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK AMBIENT SENSOR . Turn the ignition switch to OFF. Disconnect the connector from ambient sensor. Measure the resistance between terminals of ambient sensor. Terminals No. 1 - No. 2 | Is the resistance approximately 3 kohms at 25°C (77°F)? | Go to step 2 . | Replace the ambient sensor. |
| 2 CHECK INPUT SIGNAL FOR AMBIENT SENSOR . Turn the ignition to ON. Measure the voltage between connector (F78) terminals. Connector & terminal (F78) No. 1 (+) - No. 2 (-) | Is the voltage approx. 5 V? | Go to step 6 . | Go to step 3 . |
| 3 CHECK COMBINATION METER OUTPUT SIGNAL . Turn the ignition switch to OFF. Pull out the combination meter. Disconnect the connector from ambient sensor. Turn the ignition switch to ON. Measure the voltage between the combination meter connector terminals. Connector & terminal (i10) No. 24 (+) - No. 23 (-) | Is the voltage approx. 5 V? | Go to step 4 . | Go to step 6 . |
| 4 CHECK HARNESS CONNECTOR BETWEEN COMBINATION METER AND AMBIENT TEMPERATURE SENSOR . Turn the ignition switch to OFF. Disconnect the connector from combination meter. Measure the resistance of the harness between the combination meter and ambient temperature sensor. Connector & terminal (F78) No. 1 - (i10) No. 24 | Is the resistance less than 1 ohms? | Go to step 5 . | Repair the open circuit in the harness between the combination meter and ambient temperature sensor. |
| 5 CHECK HARNESS CONNECTOR BETWEEN COMBINATION METER AND AMBIENT TEMPERATURE SENSOR . Measure the resistance of the harness between the combination meter and ambient temperature sensor. Connector & terminal (F78) No. 2 - (i10) No. 23 | Is the resistance less than 1 ohms? | Replace the combination meter. | Repair the open circuit in the harness between the combination meter and ambient temperature sensor. |
| 6 CHECK HARNESS CONNECTOR BETWEEN COMBINATION METER AND AUTO A/C CONTROL MODULE . Turn the ignition switch to OFF. Disconnect the connector from the combination meter. Disconnect the auto A/C control module connector. Measure the resistance of the harness between the combination meter and auto A/C control module. Connector & terminal (i88) No. 19 - (i10) No. 26 | Is the resistance less than 1 ohms? | Go to step 7 . | Repair the open circuit in the harness between the combination meter and auto A/C control module. |
| 7 CHECK HARNESS CONNECTOR BETWEEN COMBINATION METER AND AUTO A/C CONTROL MODULE . Measure the resistance of the harness between the combination meter and auto A/C control module. Connector & terminal (i88) No. 20 - (i10) No. 27 | Is the resistance less than 1 Oft | Go to step 8 . | Repair the open circuit in the harness between the combination meter and auto A/C control module. |
| 8 CHECK POOR CONTACT . Check poor contact of auto A/C control module connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
- Blower fan speed, air flow outlet and FRESH/RECIRC do not change after turning the AUTO switch to ON.
- Failure related to the in-vehicle sensor is indicated in self-diagnosis.
Scheme 48
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK IN-VEHICLE SENSOR . Turn the ignition switch to OFF. Remove the driver's side lower cover. Disconnect the connector from in-vehicle sensor. Measure the resistance between terminals of in-vehicle sensor. Terminals No. 1 - No. 2 | Is the resistance approximately 2.2 kohms at 25°C (77°F)? | Go to step 2 . | Replace the in-vehicle sensor. |
| 2 CHECK INPUT SIGNAL FOR IN-VEHICLE SENSOR . Turn the ignition switch to ON. Measure the voltage between in-vehicle sensor harness connector terminals. Connector & terminal (i55) No. 2 (+) - No. 1 (-) | Is the voltage approx. 5 V? | Go to step 6 . | Go to step 3 . |
| 3 CHECK AUTO A/C CONTROL MODULE OUTPUT SIGNAL . Turn the ignition switch to OFF. Remove the auto A/C control module. Turn the ignition switch to ON. Measure the voltage between connector terminals of auto A/C control module. Connector & terminal (i88) No. 17(+) - (i88) No. 14 (-) | Is the voltage approx. 5 V? | Go to step 4 . | Go to step 6 . |
| 4 CHECK HARNESS BETWEEN AUTO A/C CONTROL MODULE AND IN-VEHICLE SENSOR . Turn the ignition switch to OFF. Disconnect the connector from the auto A/C control module. Measure the resistance of harness between auto A/C control module and in-vehicle sensor. Connector & terminal (i55) No. 2 - (i88) No. 17 | Is the resistance less than 1 ohms? | Go to step 5 . | Repair the harness between auto A/C control module and in-vehicle sensor. |
| 5 CHECK HARNESS BETWEEN AUTO A/C CONTROL MODULE AND IN-VEHICLE SENSOR . Measure the resistance of harness between auto A/C control module and in-vehicle sensor. Connector & terminal (i55) No. 1 - (i88) No. 14 | Is the resistance less than 1 ohms? | Go to step 6 . | Repair the harness between auto A/C control module and in-vehicle sensor. |
| 6 CHECK POOR CONTACT . Check poor contact of auto A/C control module connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
Scheme 49
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK EVAPORATOR SENSOR . Turn the ignition switch to OFF. Remove the glove box. Disconnect the connector from evaporator sensor. Measure the resistance between terminals of the evaporator sensor. Terminals No. 1 - No. 2 | Is the resistance approximately 6.2 kohms at 0°C (32°F), or approximately 3.3 kohms at 15°C (59°F)? | Go to step 2 . | Replace the evaporator sensor. |
| 2 CHECK INPUT SIGNAL FOR EVAPORATOR SENSOR . Turn the ignition switch to ON. Measure the voltage between connector (B88) terminals. Connector & terminal (B88) No. 2 (+) - No. 1 (-) | Is the voltage approx. 5 V? | Go to step 6 . | Go to step 3 . |
| 3 CHECK AUTO A/C CONTROL MODULE OUTPUT SIGNAL . Turn the ignition switch to OFF. Remove the auto A/C control module. Turn the ignition switch to ON. Measure the voltage between connector terminals of auto A/C control module. Connector & terminal (i88) No. 18 (+) - (i88) No. 14 (-) | Is the voltage approx. 5 V? | Go to step 4 . | Go to step 6 . |
| 4 CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND EVAPORATOR SENSOR . Turn the ignition switch to OFF. Disconnect the connector from the auto A/C control module. Measure the resistance of harness between auto A/C control module and evaporator sensor. Connector & terminal (B88) No. 2 - (i88) No. 18 | Is the resistance less than 1 ohms? | Go to step 5 . | Repair the open circuit of harness between auto A/C control module and evaporator sensor. |
| 5 CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND EVAPORATOR SENSOR . Measure the resistance of harness between auto A/C control module and evaporator sensor. Connector & terminal (B88) No. 1 - (i88) No. 14 | Is the resistance less than 1 ohms? | Go to step 6 . | Repair the open circuit of harness between auto A/C control module and evaporator sensor. |
| 6 CHECK POOR CONTACT . Check poor contact of auto A/C control module connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
- Sensor identifies that sunlight is at maximum. Then, A/C system is controlled to COOL side.
- Sensor identifies that sunlight is at minimum. Then, A/C system is controlled to HOT side.
Note. When the sunload sensor check is performed indoors or in the shade, it could be diagnosed as having an open circuit. Always check the sunload sensor with the sun shining on it.
Scheme 50
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK POWER SUPPLY VOLTAGE FOR SUNLOAD SENSOR . Turn the ignition switch to OFF. Disconnect the connector from sunload sensor. Turn the ignition switch to ON. Measure the power supply voltage for sun-load sensor. Connector & terminal (i51) No. 2 (+) - No. 1 (-) | Is the voltage approx. 5 V? | Go to step 4 . | Go to step 2 . |
| 2 CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND SUN-LOAD SENSOR . Turn the ignition switch to OFF. Disconnect the connector from the auto A/C control module. Measure the resistance of the harness between the auto A/C control module and sun-load sensor. Connector & terminal (i51) No. 2 - (i88) No. 16 | Is the resistance less than 1 ohms? | Go to step 3 . | Repair the harness between auto A/C control module and sunload sensor. |
| 3 CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND SUN-LOAD SENSOR . Measure the resistance of the harness between the auto A/C control module and sunload sensor. Connector & terminal (i51) No. 1 - (i88) No. 14 | Is the resistance less than 1 ohms? | Go to step 4 . | Repair the harness between auto A/C control module and sunload sensor. |
| 4 CHECK INPUT VOLTAGE FOR AUTO A/C CONTROL MODULE . Connect the connectors of sunload sensor and auto A/C control module. Turn the ignition switch to ON. Measure the voltage between connector terminals of auto A/C control module. Connector & terminal (i88) No. 16 (+) - (i88) No. 14 (-) | Is the voltage within approximately 1.0 - 4.0 V? | Go to step 5 . | Replace the sunload sensor. |
| 5 CHECK POOR CONTACT . Check poor contact of auto A/C control module connector. | Is there poor contact in connector? | Repair the connector. | Replace the auto A/C control module. |
DIAGNOSIS PROCEDURE CHART
| Symptoms | Problem parts |
|---|---|
| A/C system fails to operate. | Fuse (M/B No. 8, F/B No. 22, 31) Connector (Poor contact) Ground Auto A/C control module Blower fan motor Blower fan relay A/C relay Compressor (Magnet clutch) Evaporator sensor |
| Fuse is blown out. | Fuse (M/B No. 8, F/B No. 22, 31) Connector (Poor contact) |
| Illumination cannot dim. | Fuse (M/B No. 8, F/B No. 22, 31) Connector (Poor contact) Auto A/C control module |
| Blower fan does not rotate or fan speed cannot be controlled. | Fuse (M/B No. 8, F/B No. 22, 31) Connector (Poor contact) Ground Auto A/C control module Blower fan motor Blower fan relay |
| Unable to switch suction vents. | Connector (Poor contact) Auto A/C control module Intake door actuator |
| Unable to switch vents. | Connector (Poor contact) Auto A/C control module Mode door actuator |
| Compartment temperature does not rise. (Warm air does not come out) | Connector (Poor contact) Auto A/C control module Air mix door actuator In-vehicle sensor, ambient sensor, evaporator sensor and sunload sensor In-vehicle sensor aspirator hose |
| Compartment temperature does not lower. (Cold air does not come out) | Connector (Poor contact) Auto A/C control module Air mix door actuator A/C relay Compressor (Magnet clutch) Radiator fan motor Radiator fan relay In-vehicle sensor, ambient sensor, evaporator sensor and sunload sensor In-vehicle sensor aspirator hose |
| Compartment temperature is higher or lower than setting temperature. | Auto A/C control module Air mix door actuator In-vehicle sensor, ambient sensor, evaporator sensor and sunload sensor In-vehicle sensor aspirator hose |
| Compartment temperature does not quickly respond to setting temperature. | Air mix door actuator In-vehicle sensor, ambient sensor, evaporator sensor and sunload sensor In-vehicle sensor aspirator hose |
| Radiator fan does not rotate during A/C operation. | Radiator fan motor Radiator fan relay |
SYMPTOMS CHART