Air Conditioning: Overview Toyota RAV4 III

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1. IF ANY OF FOLLOWING CONDITIONS ARE MET, KEEP ENGINE IDLING WITH A/C ON (ENGINE SPEED AT LESS THAN 2000 RPM) FOR AT LEAST 1 MINUTE: Refrigerant gas has been refilled or A/C parts have been replaced. A long time has elapsed since the engine was stopped. NOTE: If the engine speed exceeds 2,000 RPM, the A/C compressor may be damaged.
2. DO NOT HANDLE REFRIGERANT IN ENCLOSED AREAS OR NEAR OPEN FLAMES
3. ALWAYS WEAR EYE PROTECTION
4. BE CAREFUL NOT TO GET LIQUID REFRIGERANT IN YOUR EYES OR ON YOUR SKIN If liquid refrigerant gets in your eyes or on your skin: Wash the area with lots of cold water. CAUTION: Do not rub your eyes or skin. Apply clean petroleum jelly to the skin. Go immediately to a physician or hospital for professional treatment.
5. NEVER HEAT CONTAINER OR EXPOSE IT TO OPEN FLAME
6. BE CAREFUL NOT TO DROP CONTAINER OR SUBJECT IT TO PHYSICAL SHOCKS
7. DO NOT OPERATE COMPRESSOR WITH INSUFFICIENT REFRIGERANT IN REFRIGERANT SYSTEM If there is not enough refrigerant in the refrigerant system, oil lubrication will be insufficient and compressor burnout may occur. Necessary care should be taken to avoid this.
8. DO NOT OPEN HIGH PRESSURE MANIFOLD VALVE WHILE COMPRESSOR IS OPERATING Open and close only the low pressure valve. Opening and closing the high pressure valve could cause the charging cylinder to rupture.
9. BE CAREFUL NOT TO OVERCHARGE SYSTEM WITH REFRIGERANT If the refrigerant is overcharged, it causes problems such as insufficient cooling, poor fuel economy and engine overheating.
10. DO NOT OPERATE ENGINE AND COMPRESSOR WITHOUT REFRIGERANT NOTE: This may damage the inside of the compressor.

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Communication table

COMMUNICATION CHART

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1. GENERAL The air conditioning system has the following features: In accordance with the temperature set using the temperature control switch, the air conditioning amplifier determines the outlet temperature based on the input signals from various sensors. In addition, corrections are made in accordance with the signals from the water temperature sensor to control the outlet air temperature. Controls the blower motor in accordance with the airflow volume determined by the air conditioning amplifier based on the input signals from various sensors. Automatically changes the outlets in accordance with the outlet mode ratio that is determined by the air conditioning amplifier based on the input signals from various sensors. Based on the signals from the ambient temperature sensor, this system calculates the outside temperature and indicates it in the multi-information display in the combination meter assembly. The left/right independent temperature control and neural network control make air conditioner control available to suit the persons in the driver seat and in the passenger seat. Turns the rear defogger and outside rear mirror heaters on for 15 minutes when the rear defogger switch is pressed. Turns them off if the switch is pressed while they are operating. Checks the sensors in accordance with the operation of the air conditioner switches. The air conditioning amplifier has the function of controlling the indicator lighting.
2. MODE POSITION AND DAMPER OPERATION
3. AIR OUTLET AND AIRFLOW VOLUME The size of the circle in the chart below indicates the proportion of the flow volume.

DESCRIPTION

The room temperature sensor is installed in the instrument panel to detect the room temperature and control the heater and air conditioner AUTO mode. The resistance of the room temperature sensor changes in accordance with the room temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier applies a voltage (5 V) to the room temperature sensor and reads voltage changes as changes in the resistance of the room temperature sensor.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. READ VALUE OF INTELLIGENT TESTER (ROOM TEMP) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note ROOM TEMP Room temperature sensor / Min.: -6.5°C (20.3°F) Max.: 57.25°C (135.05°F) Actual room temperature is displayed Open circuit: -6.5°C (20.3°F) Short circuit: 57.25°C (135.05°F) OK: The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY A: GO TO NEXT STEP.
2. INSPECT COOLER THERMISTOR (ROOM TEMPERATURE SENSOR) Remove the room temperature sensor. Measure the resistance of the sensor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Condition Specified Condition 1 (ST+) - 2 (ST-) 10°C (50°F) 3.00 to 3.73 k 1 (ST+) - 2 (ST-) 15°C (59°F) 2.45 to 2.88 k 1 (ST+) - 2 (ST-) 20°C (68°F) 1.95 to 2.30 k 1 (ST+) - 2 (ST-) 25°C (77°F) 1.60 to 1.80 k 1 (ST+) - 2 (ST-) 30°C (86°F) 1.28 to 1.47 k 1 (ST+) - 2 (ST-) 35°C (95°F) 1.00 to 1.22 k 1 (ST+) - 2 (ST-) 40°C (104°F) 0.80 to 1.00 k 1 (ST+) - 2 (ST-) 45°C (113°F) 0.65 to 0.85 k 1 (ST+) - 2 (ST-) 50°C (122°F) 0.50 to 0.70 k 1 (ST+) - 2 (ST-) 55°C (131°F) 0.44 to 0.60 k 1 (ST+) - 2 (ST-) 60°C (140°F) 0.36 to 0.50 k NOTE: Touching the sensor even slightly may change the resistance value. Be sure to hold the connector of the sensor. When measuring, the sensor temperature must be the same as the ambient temperature. HINT: As the temperature increases, the resistance decreases (Scheme 13) NG: REPLACE COOLER THERMISTOR (ROOM TEMPERATURE SENSOR) OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (ROOM TEMPERATURE SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the E21 sensor connector. Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E21-1 (ST+) - E37-29 (TR) Below 1 E21-2 (ST-) - E37-34 (SG-1) Below 1 E21-1 (ST+) - Body ground 1 M or higher E21-2 (ST-) - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

The ambient temperature sensor is installed in the front part of the condenser to detect the ambient temperature and control the air conditioner. The sensor is connected to the combination meter and detects fluctuations in the ambient temperature. This data is used for controlling the room temperature. The sensor sends a signal to the air conditioning amplifier via the combination meter. The resistance of the ambient temperature sensor changes in accordance with the ambient temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier applies a voltage (5 V) to the ambient temperature sensor and reads voltage changes as changes in the resistance of the ambient temperature sensor. The combination meter sends the read signal to the air conditioning amplifier via CAN communication.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. READ VALUE OF INTELLIGENT TESTER (AMBI TEMP SENS) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note AMBI TEMP SENS Ambient temperature sensor / Min.: -23.3°C (-9.94°F) Max.: 65.95°C (150.71°F) Actual ambient temperature is displayed Open circuit: -23.3°C (-9.94°F) Short circuit: 65.95°C (150.71°F) OK: The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT AMBIENT TEMPERATURE SENSOR Remove the ambient temperature sensor. Measure the resistance of the sensor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Condition Specified Condition 1 - 2 10°C (50°F) 3.00 to 3.73 k 1 - 2 15°C (50°F) 2.45 to 2.88 k 1 - 2 20°C (68°F) 1.95 to 2.30 k 1 - 2 25°C (77°F) 1.60 to 1.80 k 1 - 2 30°C (86°F) 1.28 to 1.47 k 1 - 2 35°C (95°F) 1.00 to 1.22 k 1 - 2 40°C (104°F) 0.80 to 1.00 k 1 - 2 45°C (113°F) 0.65 to 0.85 k 1 - 2 50°C (122°F) 0.50 to 0.70 k 1 - 2 55°C (131°F) 0.44 to 0.60 k 1 - 2 60°C (140°F) 0.36 to 0.50 k NOTE: Touching the sensor even slightly may change the resistance value. Be sure to hold the connector of the sensor. When measuring, the sensor temperature must be the same as the ambient temperature. HINT: As the temperature increases, the resistance decreases (Scheme 16) NG: REPLACE AMBIENT TEMPERATURE SENSOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (AMBIENT TEMPERATURE SENSOR - COMBINATION METER) Disconnect the A17 sensor connector. Disconnect the E19 meter connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition A17-2 (OT+) - E19-23 (TEMP) Below 1 A17-1 (OT-) - E19-11 (TX1+) Below 1 A17-2 (OT+) - Body ground 1 M or higher A17-1 (OT-) - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE COMBINATION METER

The No. 1 cooler thermistor (evaporator temperature sensor) is installed on the evaporator in the air conditioning unit to detect the temperature of the cooled air that has passed through the evaporator and to control the air conditioner. It sends signals to the air conditioning amplifier. The signals change in accordance with the resistance of the No. 1 cooler thermistor (evaporator temperature sensor). As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases. The air conditioning amplifier applies a voltage (5 V) to the No. 1 cooler thermistor (evaporator temperature sensor) and reads voltage changes as changes in the resistance of the No. 1 cooler thermistor (evaporator temperature sensor). This sensor is used for frost prevention.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. READ VALUE OF INTELLIGENT TESTER (EVAP FIN TEMP) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note EVAP FIN TEMP Evaporator temperature sensor / Min.: -29.7°C (-21.46°F) Max.: 59.6°C (139.28°F) Actual evaporator temperature is displayed Open circuit: -29.7°C (-21.46°F) Short circuit: 59.6°C (139.28°F) OK: The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT NO. 1 COOLER THERMISTOR (EVAPORATOR TEMPERATURE SENSOR) Remove the No. 1 cooler thermistor. Measure the resistance of the thermistor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Condition Specified Condition 1 - 2 -10°C (14°F) 7.30 to 9.10 k 1 - 2 -5°C (23°F) 5.65 to 6.95 k 1 - 2 0°C (32°F) 4.40 to 5.35 k 1 - 2 5°C (41°F) 3.40 to 4.15 k 1 - 2 10°C (50°F) 2.70 to 3.25 k 1 - 2 15°C (59°F) 2.14 to 2.58 k 1 - 2 20°C (68°F) 1.71 to 2.05 k 1 - 2 25°C (77°F) 1.38 to 1.64 k 1 - 2 30°C (86°F) 1.11 to 1.32 k NOTE: Touching the thermistor even slightly may change the resistance value. Be sure to hold the connector of the thermistor. When measuring, the thermistor temperature must be the same as the ambient temperature. HINT: As the temperature increases, the resistance decreases (Scheme 19) NG: REPLACE NO. 1 COOLER THERMISTOR OK: REPLACE AIR CONDITIONING HARNESS ASSEMBLY

The solar sensor, which is installed on the upper side of the instrument panel, detects sunlight and controls the air conditioning AUTO mode. The output voltage from the solar sensor varies in accordance with the amount of sunlight. When the sunlight increases, the output voltage increases. As the sunlight decreases, the output voltage decreases.

The air conditioning amplifier detects changes in the output voltage from the solar sensor.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. READ VALUE OF INTELLIGENT TESTER (SOLAR SENS-P) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note SOLAR SENS-P Passenger side solar sensor / Min.: 0, Max.: 255 Passenger side temperature increases as brightness increases - OK : The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT COOLER (SOLAR SENSOR) THERMISTOR Remove the solar sensor. Measure the resistance of the sensor. Connect the ohmmeter's positive (+) lead to terminal 1 and the negative (-) lead to terminal 2 of the solar sensor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Condition Specified Condition 1 (SS) - 2 (TSP) Sensor exposed to electric light Except infinity ohms 1 (SS) - 2 (TSP) Sensor covered with cloth Infinity ohms NOTE: The connection procedure for using a digital tester such as an electrical tester is shown above. When using an analog tester, connect the positive (+) lead to terminal 2 and the negative (-) lead to terminal 1 of the solar sensor. HINT: As the inspection light is moved away from the sensor, the voltage decreases. Use an incandescent light for the inspection. Position it about 30 cm (11.8 in.) from the solar sensor. NG: REPLACE COOLER (SOLAR SENSOR) THERMISTOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (SOLAR SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the F1 sensor connector. Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E37-32 (TSP) - F1-2 (TSP) Below 1 E37-31 (S5-4) - F1-1 (SS) Below 1 E37-32 (TSP) - Body ground 1 M or higher E37-31 (S5-4) - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE AIR CONDITIONING AMPLIFIER

This sensor sends 1 pulse per engine revolution to the air conditioning amplifier. If the ratio of the compressor speed divided by the engine speed is smaller than a predetermined value, the air conditioning amplifier turns the compressor off, and the indicator blinks at approximately 1 second intervals.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. CHECK AIR CONDITIONING AMPLIFIER (LOCK SIGNAL) Remove the air conditioning amplifier with its connectors still connected. Check the waveform of the amplifier connector. OK: Waveform is as shown in the illustration. (Scheme 24) ITEM AND CONTENT REFERENCE Item Content Tester Connection LOCK (E37-8) - SG-2 (E37-13) Tool Setting 500 mV/DIV., 20 msec./DIV. Condition Ignition switch ON AUTO switch ON A/C switch ON Magnetic clutch ON Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT COMPRESSOR LOCK SENSOR Disconnect the B47 compressor lock sensor connector. Measure the resistance of the sensor. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition 1 (SSR+) - 2 (SSR-) 20°C (68°F) 65 to 125 NG: REPLACE COMPRESSOR LOCK SENSOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (COMPRESSOR LOCK SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the B47 compressor lock sensor connector. Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition B47-1 (SSR+) - E37-8 (LOCK) Below 1 B47-2 (SSR-) - E37-13 (SG-2) Below 1 B47-1 (SSR+) - E37-13 (SG-2) 10 k or higher E37-8 (LOCK) - Body ground 10 k or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE AIR CONDITIONING AMPLIFIER

This DTC is output when the refrigerant pressure is either extremely low (0.19 MPa [2.0 kgf/cm 2 , 28 psi] or less) or extremely high (3.14 MPa [32.0 kgf/cm 2 , 455 psi] or more). The air conditioning pressure sensor, which is installed on the pipe of the high pressure side, detects the refrigerant pressure and sends refrigerant pressure signals to the air conditioning amplifier. The air conditioning amplifier determines the pressure from the signals in accordance with the sensor characteristics, and controls the compressor accordingly.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. CHECK REFRIGERANT Check the sight glass of the cooler unit refrigerant liquid pipe. Prepare the vehicle in accordance with the chart below. ENGINE SPEED SPECIFICATION Item Condition Engine Speed 1,500 RPM Vehicle Doors Fully open Temperature Setting MAX COLD Blower Speed HI A/C Switch ON Compare the sight glass to the following chart. PROBLEM SYMPTOMS CHART Item Symptom Amount of Refrigerant Corrective Procedures 1 Bubbles visible Insufficient* Check for gas leakage and repair if necessary Add refrigerant until bubbles disappear 2 No bubbles visible Empty, insufficient or too much Refer to items 3 and 4 3 No temperature difference between compressor inlet and outlet Empty or nearly empty Check for gas leakage with gas leak detector and repair if necessary Add refrigerant until bubbles disappear 4 Considerable temperature difference between compressor inlet and outlet Correct or too much Refer to items 5 and 6 5 Refrigerant becomes clear immediately after A/C turned OFF Too much Drain or discharge refrigerant Bleed air and supply proper amount of purified refrigerant 6 Refrigerant foams and then becomes clear immediately after A/C turned OFF Correct - HINT: *: If the ambient temperature is higher than usual but cooling is sufficient, bubbles in the sight glass are permissible. NG: CHARGE REFRIGERANT OK: GO TO NEXT STEP.
2. READ VALUE OF INTELLIGENT TESTER (REG PRESS SENS) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note REG PRESS SENS Regulator pressure sensor / Min.: 0 MPaG Max.: 3.187 MPaG Actual regulator pressure is displayed - OK: The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the A21 pressure sensor connector. Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition A21-3 (+) - E37-10 (S5-3) Below 1 A21-2 (PR) - E37-9 (PRE) Below 1 A21-1 (-) - E37-13 (SG-2) Below 1 A21-3 (+) - Body ground 1 M or higher A21-2 (PR) - Body ground 1 M or higher A21-1 (-) - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
4. CHECK AIR CONDITIONING AMPLIFIER Remove the air conditioning amplifier with its connectors still connected. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition E37-13 (SG-2) - Body ground Below 1 Turn the ignition switch ON. Measure the voltage of the wire harness side connector. (Scheme 30) Standard voltage TERMINALS VOLTAGE SPECIFICATION Tester Connection Specified Condition E37-10 (S5-3) - E37-13 (SG-2) 4.5 to 5.5 V NG: REPLACE AIR CONDITIONING AMPLIFIER OK: GO TO NEXT STEP.
5. INSPECT AIR CONDITIONING PRESSURE SENSOR Turn the A/C switch ON. Disconnect the A21 sensor connector. Connect the three 1.5 V dry cell batteries' positive (+) lead to terminal 3 and the negative (-) lead to terminal 1. Then connect the voltmeter's positive (+) lead to terminal 2 and the negative (-) lead to terminal 1. Measure the voltage. OK: The voltage changes in accordance with the refrigerant pressure as shown in the graph. NG: REPLACE AIR CONDITIONING PRESSURE SENSOR OK: REPLACE AIR CONDITIONING AMPLIFIER

The solar sensor, which is installed on the upper side of the instrument panel, detects sunlight and controls the air conditioning AUTO mode. The output voltage from the solar sensor varies in accordance with the amount of sunlight. When the sunlight increases, the output voltage increases. As the sunlight decreases, the output voltage decreases.

The air conditioning amplifier detects changes in the output voltage from the solar sensor.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. READ VALUE OF INTELLIGENT TESTER (SOLAR SENSOR D SIDE) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note SOLAR SENS-D Driver side solar sensor / Min.: 0, Max.: 255 Driver side temperature increases as brightness increases - OK : The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT SOLAR SENSOR Remove the solar sensor. Measure the resistance of the sensor. Connect the ohmmeter's positive (+) lead to terminal 1 and the negative (-) lead to terminal 3 of the solar sensor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Condition Specified Condition 1 (SS) - 3 (TSD) Sensor exposed to electric light Except infinity ohms 1 (SS) - 3 (TSD) Sensor covered with cloth Infinity ohms (No continuity) NOTE: The connection procedure for using a digital tester such as an electrical tester is shown above. When using an analog tester , connect the positive (+) lead to terminal 3 and the negative (-) lead to terminal 1 of the solar sensor. HINT: As the inspection light is moved away from the sensor, the voltage decreases. Use an incandescent light for the inspection. Position it about 30 cm (11.8 in.) from the solar sensor. NG: REPLACE SOLAR SENSOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (SOLAR SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the F1 sensor connector. Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E37-33 (TSD) - F1-3 (TSD) Below 1 E37-31 (S5-4) - F1-1 (SS) Below 1 E37-33 (TSD) - Body ground 1 M or higher E37-31 (S5-4) - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE AIR CONDITIONING AMPLIFIER

The air mix damper servo sends pulse signals to indicate the damper position to the air conditioning amplifier. The air conditioning amplifier activates the motor (normal or reverse) based on these signals to move the air mix damper (passenger seat) to the appropriate position. This adjusts the amount of air passing through the heater core after passing the evaporator and controls the temperature of the blown air.

HINT

Confirm that there are no mechanical problems because this DTC can be output when either a damper link or damper is mechanically locked.

DTC DETECTION CONDITION AND TROUBLE AREA

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The damper servo (air inlet control) sends pulse signals to indicate the damper position to the air conditioning amplifier. The air conditioning amplifier activates the motor (normal or reverse) based on these signals to move the air inlet control damper to the appropriate position, which controls the intake air settings (FRESH, FRESH / RECIRCULATION and RECIRCULATION).

HINT

Confirm that there are no mechanical problems because this DTC can be output when either a damper link or damper is mechanically locked.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 36

The damper servo sends pulse signals to indicate the damper position to the air conditioning amplifier. The air conditioning amplifier activates the motor (normal or reverse) based on these signals to move the mode damper to the appropriate position, which controls the air outlet modes.

HINT

Confirm that there are no mechanical problems because this DTC can be output when either a damper link or damper is mechanically locked.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 37

The air mix damper servo sends pulse signals to indicate the damper position to the air conditioning amplifier. The air conditioning amplifier activates the motor (normal or reverse) based on these signals to move the air mix damper (driver seat) to the appropriate position. This adjusts the amount of air passing through the heater core after passing the evaporator and controls the temperature of the blown air.

HINT

Confirm that there are no mechanical problems because this DTC can be output when either a damper link or damper is mechanically locked.

DTC DETECTION CONDITION AND TROUBLE AREA

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In this circuit, the compressor receives a refrigerant compression demand signal from the air conditioning amplifier. Based on this signal, the compressor changes the degree of refrigerant compression.

DTC DETECTION CONDITION AND TROUBLE AREA

HINT

*: Compressor and pulley for 2AZ-FE, compressor and magnetic clutch for 2GR-FE

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1. READ VALUE OF INTELLIGENT TESTER (REG CTRL CURRNT) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the items below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note REG CTRL CURRNT Regulator control current / Min.: 0 A Max.: 0.997 A Value changes between 0 A and 0.997 A in accordance with A/C compressor operation - OK : The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT A/C COMPRESSOR Disconnect the A/C compressor clutch connector. Measure the resistance of the connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition 1 (SOL-) - 2 (SOL+) 25°C (77°F) 10.1 to 11.1 NG: REPLACE A/C COMPRESSOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (A/C COMPRESSOR - AIR CONDITIONING AMPLIFIER) Disconnect the B23 A/C compressor connector. Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition B23-2 (SOL+) - E37-2 (SOL+) Below 1 B23-2 (SOL+) - Body Ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
4. CHECK WIRE HARNESS (A/C COMPRESSOR - BODY GROUND) Disconnect the B23 A/C compressor connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition B23-1 (SOL-) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE AIR CONDITIONING AMPLIFIER

The air conditioning harness connects the air conditioning amplifier and the servos. The air conditioning amplifier supplies power and sends operation instructions to each servo through the air conditioning harness. Each servo sends damper position information to the air conditioning amplifier.

DTC DETECTION CONDITION AND TROUBLE AREA

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1. CHECK AIR CONDITIONING AMPLIFIER Remove the air conditioning amplifier with its connectors still connected. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition c1-2 (BUS G) - Body ground Below 1 NG: CHECK GROUND LINE AND AIR CONDITIONING AMPLIFIER OK: GO TO NEXT STEP.
2. CHECK AIR CONDITIONING AMPLIFIER Remove the air conditioning amplifier with its connectors still connected. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION Tester Connection Condition Specified Condition c1-2 (BUS G) - c1-4 (B BUS) Ignition switch ON 11 to 13 V c1-2 (BUS G) - c1-3 (BUS) Ignition switch ON Pulse generation NG: REPLACE AIR CONDITIONING AMPLIFIER OK: REPLACE AIR CONDITIONING HARNESS ASSEMBLY

The air conditioning amplifier communicates data with the ECM and combination meter through the CAN communication system.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 46

This circuit consists of the air conditioning control and the air conditioning amplifier. When the air conditioning control is operated, signals are transmitted to the air conditioning amplifier through the LIN communication system.

If the LIN communication system malfunctions, the air conditioning amplifier does not operate even if the air conditioning control is operated.

Scheme 47

Scheme 48

Scheme 49

Scheme 50

1. CHECK WIRE HARNESS (AIR CONDITIONING CONTROL ASSEMBLY - BODY GROUND) Disconnect the air conditioning control assembly connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E23-7 (GND) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
2. CHECK WIRE HARNESS (AIR CONDITIONING CONTROL ASSEMBLY - BATTERY) Disconnect the E23 air conditioning control assembly connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E23-7 (GND) - E23-2 (IG+) Ignition switch ON 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - AIR CONDITIONING CONTROL) Disconnect the E23 control connector. Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E37-37 (LIN1) - E23-11 (LIN1) Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
4. REPLACE AIR CONDITIONING AMPLIFIER Replace the air conditioning control with a new or properly functioning one. Operate the air conditioning control to check that it functions properly. Result RESULT REFERENCE Result Proceed to Air conditioning control malfunctions A Air conditioning control functions properly B B: END (AIR CONDITIONING CONTROL ASSEMBLY IS FAULTY) A: REPLACE AIR CONDITIONING AMPLIFIER

The blower motor is operated by signals from the air conditioning amplifier. Blower motor speed signals are transmitted in accordance with changes in the duty ratio.

Scheme 51

Scheme 52

Scheme 53

Scheme 54

Scheme 55

Scheme 56

Scheme 57

1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (BLOWER MOTOR) Connect the intelligent tester to (with CAN VIM) the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the ACTIVE TEST, and then check that the blower motor operates. Air conditioning amplifier ACTIVE TEST DETAIL Item Test Details / Display Diagnostic Note BLOWER MOTOR Blower motor / Min.: 0, Max.: 31 - Result RESULT REFERENCE Result Proceed to NG (blower motor does not operate) A NG (blower motor operates but does not change speed) B OK C B: Go to step 6 C: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE A: GO TO NEXT STEP.
2. INSPECT FUSE (HTR) Remove the HTR H-fuse from the engine room No. 2 relay block. Measure the resistance of the H-fuse. Standard resistance: Below 1 NG: REPLACE FUSE OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (BLOWER MOTOR - BODY GROUND) Disconnect the E53 motor connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E53-1 (GND) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
4. CHECK WIRE HARNESS (BLOWER MOTOR - BATTERY) Disconnect the E53 motor connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E53-3 (+B) - Body ground Ignition switch ON 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
5. CHECK BLOWER W/FAN MOTOR SUB-ASSEMBLY Disconnect the E37 amplifier connector. Connect the E53 motor connector. Measure the voltage of the connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION Tester Connection Condition Specified Condition E53-2 (SI) - Body ground Ignition switch ON 4.5 to 5.5 V NG: REPLACE BLOWER W/FAN MOTOR SUB-ASSEMBLY OK: GO TO NEXT STEP.
6. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND) Disconnect the E37 amplifier connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E37-23 (BLW) - Body ground Ignition switch ON Blower switch OFF 4.5 to 5.5 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
7. CHECK AIR CONDITIONING AMPLIFIER Remove the air conditioning amplifier with its connectors still connected. Check the waveform of the amplifier connector. OK: Waveform is as shown in the illustration. (Scheme 57) HINT: The waveform varies with the blower level. ITEM AND CONTENT REFERENCE Item Content Tester Connection BLW (E37-23) - GND (E37-14) Tool Setting 1 V/DIV., 500 msec./DIV. Condition Ignition switch ON Blower switch LO NG: REPLACE AIR CONDITIONING AMPLIFIER OK: REPLACE BLOWER W/FAN MOTOR SUB-ASSEMBLY

When the A/C switch is turned on, the magnetic clutch ON signal is sent from the air conditioning amplifier. Then the MG CLT relay turns on to operate the magnetic clutch.

Scheme 58

Scheme 59

Scheme 60

Scheme 61

Scheme 62

1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (A/C MAG CLUTCH) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the ACTIVE TEST and then check that the compressor magnetic relay operates. Air conditioning amplifier ACTIVE TEST DETAIL Item Test Details / Display (Range) Diagnostic Note A/C MAG CLUTCH Magnetic clutch relay / OFF, ON Operating sound can be heard OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE NG: GO TO NEXT STEP.
2. INSPECT FUSE (ECU-IG1) Remove the ECU-IG1 fuse from the instrument panel junction block. Measure the resistance of the fuse. Standard resistance: Below 1 NG: REPLACE FUSE OK: GO TO NEXT STEP.
3. INSPECT MAGNETIC CLUTCH RELAY (Marking: MG CLT) Remove the magnetic clutch relay from the engine room No. 1 relay block. Measure the resistance of the relay. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition 3 - 5 10 k or higher 3 - 5 Below 1 (when battery voltage is applied to terminals 1 and 2) NG: REPLACE MAGNETIC CLUTCH RELAY OK: GO TO NEXT STEP.
4. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY) Disconnect the E37 amplifier connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E37-20 (MGC) - Body ground Ignition switch ON 10 to 14 V E37-20 (MGC) - Body ground Ignition switch OFF Below 1 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
5. CHECK AIR CONDITIONING AMPLIFIER (MGC VOLTAGE) Remove the air conditioning amplifier with its connectors still connected. Measure the voltage of the connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION Tester Connection Condition Specified Condition E37-20 (MGC) - Body ground Ignition switch ON A/C switch OFF 10 to 14 V E37-20 (MGC) - Body ground Ignition switch ON A/C switch ON Below 1.5 V NG: REPLACE AIR CONDITIONING AMPLIFIER OK: GO TO NEXT STEP.
6. CHECK MAGNETIC CLUTCH Disconnect the B47 magnetic clutch connector. Connect the battery's positive (+) lead to terminal 3 of the magnetic clutch and the negative (-) lead to the body ground. OK : Magnetic clutch is engaged. NG: REPLACE MAGNETIC CLUTCH OK: REPAIR OR REPLACE WIRE HARNESS (MAGNETIC CLUTCH - ECU-IG1)

This is the main power source supplied to the air conditioning amplifier when the ignition switch is ON (IG). This power source is used for operating components, such as the air conditioning amplifier and servo motors.

Scheme 63

Scheme 64

Scheme 65

1. INSPECT FUSE (ECU-IG2) Remove the ECU-IG2 fuse from the instrument panel junction block. Measure the resistance of the fuse. Standard resistance: Below 1 NG: REPLACE FUSE OK: GO TO NEXT STEP.
2. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY) Disconnect the E37 amplifier connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E37-1 (IG+) - Body ground Ignition switch ON 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND) Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E37-14 (GND) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

This is the back-up power source circuit for the air conditioning amplifier. Power is supplied even when the ignition switch is turned OFF and is used for functions such as the diagnostic trouble code memory.

Scheme 66

Scheme 67

Scheme 68

1. INSPECT FUSE (ECU-B2) Remove the ECU-B2 fuse from the engine room No. 2 relay block. Measure the resistance of the fuse. Standard resistance: Below 1 NG: REPLACE FUSE OK: GO TO NEXT STEP.
2. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY) Disconnect the E37 amplifier connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E37-21 (B) - Body ground 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND) Disconnect the E37 amplifier connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E37-14 (GND) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

Scheme 69

Scheme 70

1. IF ANY OF FOLLOWING CONDITIONS ARE MET, KEEP ENGINE IDLING WITH A/C ON (ENGINE SPEED AT LESS THAN 2000 RPM) FOR AT LEAST 1 MINUTE: Refrigerant gas has been refilled or A/C parts have been replaced. A long time has elapsed since the engine was stopped. NOTE: If the engine speed exceeds 2,000 RPM, the A/C compressor may be damaged.
2. DO NOT HANDLE REFRIGERANT IN ENCLOSED AREAS OR NEAR OPEN FLAMES
3. ALWAYS WEAR EYE PROTECTION
4. BE CAREFUL NOT TO GET LIQUID REFRIGERANT IN YOUR EYES OR ON YOUR SKIN If liquid refrigerant gets in your eyes or on your skin: Wash the area with lots of cold water. CAUTION: Do not rub your eyes or skin. Apply clean petroleum jelly to the skin. Go immediately to a physician or hospital for professional treatment.
5. NEVER HEAT CONTAINER OR EXPOSE IT TO OPEN FLAME
6. BE CAREFUL NOT TO DROP CONTAINER OR SUBJECT IT TO PHYSICAL SHOCKS
7. DO NOT OPERATE COMPRESSOR WITH INSUFFICIENT REFRIGERANT IN REFRIGERANT SYSTEM If there is not enough refrigerant in the refrigerant system, oil lubrication will be insufficient and compressor burnout may occur. Necessary care should be taken to avoid this.
8. DO NOT OPEN HIGH PRESSURE MANIFOLD VALVE WHILE COMPRESSOR IS OPERATING Open and close only the low pressure valve. Opening and closing the high pressure valve could cause the charging cylinder to rupture.
9. BE CAREFUL NOT TO OVERCHARGE SYSTEM WITH REFRIGERANT If the refrigerant is overcharged, it causes problems such as insufficient cooling, poor fuel economy and engine overheating.
10. DO NOT OPERATE ENGINE AND COMPRESSOR WITHOUT REFRIGERANT NOTE: This may damage the inside of the compressor.

Scheme 71

Scheme 72

Scheme 73

Scheme 74

Communication table

COMMUNICATION CHART

Scheme 75

Scheme 76

Scheme 77

Scheme 78

1. GENERAL The air conditioning system has the following features: The air conditioning amplifier controls the operation of parts, such as the A/C compressor, automatically in accordance with the operating conditions of the air conditioning system.
2. MODE POSITION AND DAMPER OPERATION
3. AIR OUTLET AND AIRFLOW VOLUME The circle size in the chart indicates the proportion of the flow volume.

The ambient temperature sensor is installed in the front part of the condenser to detect the ambient temperature and control the air conditioner. The sensor is connected to the combination meter and detects fluctuations in the ambient temperature. This data is used for controlling the room temperature. The sensor sends a signal to the air conditioning amplifier via the combination meter. The resistance of the ambient temperature sensor changes in accordance with the ambient temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier applies a voltage (5 V) to the ambient temperature sensor and reads voltage changes as changes in the resistance of the ambient temperature sensor. The combination meter sends the read signal to the air conditioning amplifier via CAN communication.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 79

Scheme 80

Scheme 81

1. READ VALUE OF INTELLIGENT TESTER (AMBI TEMP SENS) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note AMBI TEMP SENS Ambient temperature sensor / Min.: -23.3°C (-9.94°F) Max.: 65.95°C (150.71°F) Actual ambient temperature is displayed Open circuit: -23.3°C (-9.94°F) Short circuit: 65.95°C (150.71°F) OK: The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT AMBIENT TEMPERATURE SENSOR Remove the ambient temperature sensor (Scheme 80) Measure the resistance of the sensor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Condition Specified Condition 1 - 2 10°C (50°F) 3.00 to 3.73 k 1 - 2 15°C (50°F) 2.45 to 2.88 k 1 - 2 20°C (68°F) 1.95 to 2.30 k 1 - 2 25°C (77°F) 1.60 to 1.80 k 1 - 2 30°C (86°F) 1.28 to 1.47 k 1 - 2 35°C (95°F) 1.00 to 1.22 k 1 - 2 40°C (104°F) 0.80 to 1.00 k 1 - 2 45°C (113°F) 0.65 to 0.85 k 1 - 2 50°C (122°F) 0.50 to 0.70 k 1 - 2 55°C (131°F) 0.44 to 0.60 k 1 - 2 60°C (140°F) 0.36 to 0.50 k NOTE: Touching the sensor even slightly may change the resistance value. Be sure to hold the connector of the sensor. When measuring, the sensor temperature must be the same as the ambient temperature. HINT: As the temperature increases, the resistance decreases (Scheme 80) NG: REPLACE AMBIENT TEMPERATURE SENSOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (AMBIENT TEMPERATURE SENSOR - COMBINATION METER) Disconnect the A17 sensor connector. Disconnect the E19 meter connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition A17-2 (OT+) - E19-23 (TEMP) Below 1 A17-1 (OT-) - E19-11 (TX1+) Below 1 A17-2 (OT+) - Body ground 1 M or higher A17-1 (OT-) - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP. REPLACE COMBINATION METER

The No. 1 cooler thermistor (evaporator temperature sensor) is installed on the evaporator in the air conditioning unit to detect the temperature of the cooled air that has passed through the evaporator and to control the air conditioner. It sends signals to the air conditioning amplifier. The signals change in accordance with the resistance of the No. 1 cooler thermistor (evaporator temperature sensor). As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases. The air conditioning amplifier applies a voltage (5 V) to the No. 1 cooler thermistor (evaporator temperature sensor) and reads voltage changes as changes in the resistance of the No. 1 cooler thermistor (evaporator temperature sensor). This sensor is used for frost prevention.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 82

Scheme 83

Scheme 84

1. READ VALUE OF INTELLIGENT TESTER (EVAP FIN TEMP) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note EVAP FIN TEMP Evaporator temperature sensor / Min.: -29.7°C (-21.46°F) Max.: 59.6°C (139.28°F) Actual evaporator temperature is displayed Open circuit: -29.7°C (-21.46°F) Short circuit: 59.6°C (139.28°F) OK: The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT NO. 1 COOLER THERMISTOR (EVAPORATOR TEMPERATURE SENSOR) Remove the No. 1 cooler thermistor. Measure the resistance of the thermistor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Condition Specified Condition 1 - 2 -10°C (14°F) 7.30 to 9.10 k 1 - 2 -5°C (23°F) 5.65 to 6.95 k 1 - 2 0°C (32°F) 4.40 to 5.35 k 1 - 2 5°C (41°F) 3.40 to 4.15 k 1 - 2 10°C (50°F) 2.70 to 3.25 k 1 - 2 15°C (59°F) 2.14 to 2.58 k 1 - 2 20°C (68°F) 1.71 to 2.05 k 1 - 2 25°C (77°F) 1.38 to 1.64 k 1 - 2 30°C (86°F) 1.11 to 1.32 k NOTE: Touching the thermistor even slightly may change the resistance value. Be sure to hold the connector of the thermistor. When measuring, the thermistor temperature must be the same as the ambient temperature. HINT: As the temperature increases, the resistance decreases (Scheme 83) NG: REPLACE NO. 1 COOLER THERMISTOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (NO. 1 COOLER THERMISTOR - AIR CONDITIONING AMPLIFIER) Disconnect the E33 No. 1 cooler thermistor connector. Disconnect the E36 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E33-1 - E36-22 (TE) Below 1 E33-2 - E36-23 (SG-3) Below 1 E33-1 - Body ground 1 M or higher E33-2 - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE AIR CONDITIONING AMPLIFIER

This sensor sends 1 pulse per engine revolution to the air conditioning amplifier. If the ratio of the compressor speed divided by the engine speed is smaller than a predetermined value, the air conditioning amplifier turns the compressor off, and the indicator blinks at approximately 1 second intervals.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 85

Scheme 86

Scheme 87

Scheme 88

1. CHECK AIR CONDITIONING AMPLIFIER (LOCK SIGNAL) Remove the air conditioning amplifier with its connectors still connected. (Scheme 86) Check the waveform of the amplifier connector. OK: Waveform is as shown in the illustration. ITEM AND CONTENT REFERENCE Item Content Tester Connection LOCK (E36-3) - SG-2 (E36-10) Tool Setting 500 mV/DIV., 20 msec./DIV. Condition Ignition switch ON A/C switch ON Magnetic clutch ON Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
2. INSPECT COMPRESSOR LOCK SENSOR Disconnect the B47 compressor lock sensor connector. Measure the resistance of the sensor. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition 1 (SSR+) - 2 (SSR-) 20°C (68°F) 65 to 125 NG: REPLACE COMPRESSOR LOCK SENSOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (COMPRESSOR LOCK SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the B47 compressor lock sensor connector. Disconnect the E36 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition B47-1 (SSR+) - E36-3 (LOCK) Below 1 B47-2 (SSR-) - E36-10 (SG-2) Below 1 B47-1 (SSR+) - E36-10 (SG-2) 10 k or higher E36-3 (LOCK) - Body ground 10 k or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE AIR CONDITIONING AMPLIFIER

This DTC is output when the refrigerant pressure is either extremely low (0.19 MPa [2.0 kgf/cm 2 , 28 psi] or less) or extremely high (3.14 MPa [32.0 kgf/cm 2 , 455 psi] or more). The air conditioning pressure sensor, which is installed on the pipe of the high pressure side, detects the refrigerant pressure and sends refrigerant pressure signals to the air conditioning amplifier. The air conditioning amplifier determines the pressure from the signals in accordance with the sensor characteristics, and controls the compressor accordingly.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 89

Scheme 90

Scheme 91

Scheme 92

Scheme 93

1. CHECK REFRIGERANT Check the sight glass of the cooler unit refrigerant liquid pipe. Prepare the vehicle in accordance with the chart below. ENGINE SPEED SPECIFICATION Item Condition Engine Speed 1,500 RPM Vehicle Doors Fully open Temperature Setting MAX COLD Blower Speed HI A/C Switch ON Compare the sight glass to the following chart. PROBLEM SYMPTOMS CHART Item Symptom Amount of Refrigerant Corrective Procedures 1 Bubbles visible Insufficient* Check for gas leakage and repair if necessary Add refrigerant until bubbles disappear 2 No bubbles visible Empty, insufficient or too much Refer to items 3 and 4 3 No temperature difference between compressor inlet and outlet Empty or nearly empty Check for gas leakage with gas leak detector and repair if necessary Add refrigerant until bubbles disappear 4 Considerable temperature difference between compressor inlet and outlet Correct or too much Refer to items 5 and 6 5 Refrigerant becomes clear immediately after A/C turned OFF Too much Drain or discharge refrigerant Bleed air and supply proper amount of purified refrigerant 6 Refrigerant foams and then becomes clear immediately after A/C turned OFF Correct - HINT: *: If the ambient temperature is higher than usual but cooling is sufficient, bubbles in the sight glass are permissible. NG: CHARGE REFRIGERANT OK: GO TO NEXT STEP.
2. READ VALUE OF INTELLIGENT TESTER (REG PRESS SENS) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester. Air conditioning amplifier DATA LIST DETAIL Item Measurement Item / Display (Range) Normal Condition Diagnostic Note REG PRESS SENS Regulator pressure sensor / Min.: 0 MPaG Max.: 3.187 MPaG Actual regulator pressure is displayed - OK: The display is as specified in the normal condition column. Result RESULT REFERENCE Result Proceed to NG A OK (Checking from the PROBLEM SYMPTOMS TABLE) B OK (Checking from the DTC) C B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE C: REPLACE AIR CONDITIONING AMPLIFIER A: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the A21 pressure sensor connector. Disconnect the E36 amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition A21-3 (+) - E36-7 (S5-3) Below 1 A21-2 (PR) - E36-12 (PRE) Below 1 A21-1 (-) - E36-10 (SG-2) Below 1 A21-3 (+) - Body ground 1 M or higher A21-2 (PR) - Body ground 1 M or higher A21-1 (-) - Body ground 1 M or higher NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
4. CHECK AIR CONDITIONING AMPLIFIER Remove the air conditioning amplifier with its connectors still connected. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition E36-10 (SG-2) - Body ground Below 1 Turn the ignition switch ON. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION Tester Connection Specified Condition E36-7 (S5-3) - E36-10 (SG-2) 4.5 to 5.5 V NG: REPLACE AIR CONDITIONING AMPLIFIER OK: GO TO NEXT STEP.
5. INSPECT AIR CONDITIONING PRESSURE SENSOR Turn the A/C switch ON. Disconnect the A21 sensor connector. Connect the three 1.5 V dry cell batteries' positive (+) lead to terminal 3 and the negative (-) lead to terminal 1. Then connect the voltmeter's positive (+) lead to terminal 2 and the negative (-) lead to terminal 1. Measure the voltage. OK: The voltage changes in accordance with the refrigerant pressure as shown in the graph. NG: REPLACE AIR CONDITIONING PRESSURE SENSOR OK: REPLACE AIR CONDITIONING AMPLIFIER

In this circuit, the compressor receives a refrigerant compression demand signal from the air conditioning amplifier. Based on this signal, the compressor changes the degree of refrigerant compression.

DTC DETECTION CONDITION AND TROUBLE AREA

The air conditioning amplifier communicates data with the ECM and combination meter through the CAN communication system.

DTC DETECTION CONDITION AND TROUBLE AREA

Scheme 94

When the heater control (blower switch) is set to position 1 or higher, the contact of the HTR relay is closed, current flows to the blower motor, and the blower motor operates. The blower motor speed can be changed by exchanging the ground and the blower resistor circuit with the heater control (blower switch).

Scheme 95

Scheme 96

Scheme 97

Scheme 98

Scheme 99

Scheme 100

Scheme 101

Scheme 102

Scheme 103

Scheme 104

Scheme 105

1. INSPECT FUSE (HTR) Remove the HTR fuse from the engine room No. 2 relay block. Measure the resistance of the fuse. Standard resistance: Below 1 NG: REPLACE FUSE OK: GO TO NEXT STEP.
2. INSPECT HEATER RELAY (Marking: HTR) Remove the heater relay from the instrument panel junction block. Measure the resistance of the relay. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition 3 - 4 Below 1 3 - 5 10 k or higher 3 - 4 10 k or higher (when battery voltage is applied to terminals 1 and 2) 3 - 5 Below 1 (when battery voltage is applied to terminals 1 and 2) NG: REPLACE HEATER RELAY OK: GO TO NEXT STEP.
3. INSPECT BLOWER MOTOR Disconnect the E54 motor connector. Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1, then check that the blower motor operates smoothly. OK: The blower motor operates smoothly. Measure the current. Standard current TERMINALS CURRENT SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E54-1 - E54-2 Blower motor operates 1 to 3 A NG: REPLACE BLOWER MOTOR OK: GO TO NEXT STEP.
4. CHECK WIRE HARNESS (HEATER CONTROL (BLOWER SWITCH) - BATTERY) Disconnect the E24 heater control connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E24-4 (LO) - Body ground Ignition switch ON 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
5. INSPECT HEATER CONTROL (BLOWER SWITCH) Remove the heater control. Measure the resistance of the switch. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Switch Position Specified Condition ALL - 5 (E) 0 10 k or higher 4 (LO) - 5 (E) 1 Below 1 4 (LO) - 5 (E) - 9 (M1) 1 to 2 Below 1 4 (LO) - 5 (E) - 9 (M1) 2 Below 1 (LO) - (E) - 9 (M1) - 10 (M2) 2 to 3 Below 1 4 (LO) - 5 (E) - 10 (M2) 3 Below 1 4 (LO) - 5 (E) - 10 (M2) - 6(HI) 3 to 4 Below 1 4 (LO) - 5 (E) - 6 (HI) 4 Below 1 NG: REPLACE HEATER CONTROL OK: GO TO NEXT STEP.
6. INSPECT BLOWER RESISTOR Remove the blower resistor. Measure the resistance of the resistor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition E55-4 (E) - E55-1 (HI) 3.12 to 3.60 E55-4 (E) - E55-3 (M2) 1.45 to 1.67 E55-4 (E) - E55-2 (M1) 0.52 to 0.60 NG: REPLACE BLOWER RESISTOR OK: GO TO NEXT STEP.
7. CHECK WIRE HARNESS (HEATER CONTROL (BLOWER SWITCH) - BLOWER RESISTOR) Disconnect the E24 heater control connector. Disconnect the E55 blower resistor connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E24-6 (HI) - E55-1 (HI) Below 1 E24-9 (M1) - E55-2 (M1) Below 1 E24-10 (M2) - E55-3 (M2) Below 1 E24-5 (E) - Body ground Below 1 E55-4 (E) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
8. CHECK WIRE HARNESS (BLOWER RESISTOR - BLOWER MOTOR) Disconnect the E55 blower resistor connector. Disconnect the E54 motor connector. Measure the resistance of the wire harness side connectors. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E55-4 (E) - E54-1 Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
9. CHECK WIRE HARNESS (BLOWER MOTOR - BODY GROUND) Disconnect the E54 motor connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E54-2 - Body ground Below 1 Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION Tester Connection Condition Specified Condition E54-2 - Body ground Ignition switch ON Heater control (blower switch) 1 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
10. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY) Disconnect the E36 amplifier connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E36-21 (SBLW) - Body ground Ignition switch ON Heater control (blower switch) 0 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
11. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND) Disconnect the E36 amplifier connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E36-24 (GND) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

When the A/C switch is turned on, the magnetic clutch ON signal is sent from the air conditioning amplifier. Then the MG CLT relay turns on to operate the magnetic clutch.

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1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (A/C MAG CLUTCH) Connect the intelligent tester (with CAN VIM) to the DLC3. Turn the ignition switch ON and turn the intelligent tester main switch ON. Select the item below in the ACTIVE TEST and then check that the compressor magnetic relay operates. Air conditioning amplifier ACTIVE TEST DETAIL Item Test Details / Display (Range) Diagnostic Note A/C MAG CLUTCH Magnetic clutch relay / OFF, ON Operating sound can be heard OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE NG: GO TO NEXT STEP.
2. INSPECT FUSE (ECU-IG1) Remove the ECU-IG1 fuse from the instrument panel junction block. Measure the resistance of the fuse. Standard resistance: Below 1 NG: REPLACE FUSE OK: GO TO NEXT STEP.
3. INSPECT MAGNETIC CLUTCH RELAY (Marking: MG CLT) Remove the magnetic clutch relay from the engine room No. 1 relay block. Measure the resistance of the relay. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition 3 - 5 10 k or higher 3 - 5 Below 1 (when battery voltage is applied to terminals 1 and 2) NG: REPLACE MAGNETIC CLUTCH RELAY
4. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY) Disconnect the E36 amplifier connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E36-15 (MGC) - Body ground Ignition switch ON 10 to 14 V E36-15 (MGC) - Body ground Ignition switch OFF Below 1 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
5. CHECK AIR CONDITIONING AMPLIFIER (MGC VOLTAGE) Remove the air conditioning amplifier with its connectors still connected. Measure the voltage of the connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION Tester Connection Condition Specified Condition E36-15 (MGC) - Body ground Ignition switch ON A/C switch OFF 10 to 14 V E36-15 (MGC) - Body ground Ignition switch ON A/C switch ON Below 1 V NG: REPLACE AIR CONDITIONING AMPLIFIER OK: GO TO NEXT STEP.
6. CHECK MAGNETIC CLUTCH Disconnect the B47 magnetic clutch connector. Connect the battery's positive (+) lead to terminal 3 of the magnetic clutch and the negative (-) lead to the body ground. OK: Magnetic clutch is engaged. NG: REPLACE MAGNETIC CLUTCH OK: REPAIR OR REPLACE WIRE HARNESS (MAGNETIC CLUTCH - ECU-IG1)

This is the main power source supplied to the air conditioning amplifier when the ignition switch is ON. This power source is used for operating components, such as the air conditioning amplifier and servo motors.

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1. INSPECT FUSE (ECU-IG2) Remove the ECU-IG2 fuse from the instrument panel junction block. Measure the resistance of the fuse. Standard resistance: Below 1 NG: REPLACE FUSE OK: GO TO NEXT STEP.
2. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY) Disconnect the E36 amplifier connector. Measure the voltage of the wire harness side connector. Standard voltage TERMINALS VOLTAGE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Condition Specified Condition E36-14 (IG+) - Body ground Ignition switch ON 10 to 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: GO TO NEXT STEP.
3. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND) Disconnect the E36 amplifier connector. Measure the resistance of the wire harness side connector. Standard resistance TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED) Tester Connection Specified Condition E36-24 (GND) - Body ground Below 1 NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

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1. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET This method uses a manifold gauge set to locate problem areas. Read the manifold gauge pressure when these conditions are established. Test conditions: Temperature at the air inlet is 30 to 35°C (86 to 95°F). Engine is running at 1,500 RPM. All doors are fully open. Blower speed control switch is at HI. A/C switch is ON. Gauge readings (Reference). Normally functioning refrigeration system Gauge reading REFRIGERANT VOLUME SPECIFICATION Pressure side Refrigerant volume Low 0.15 to 0.25 MPa (1.5 to 2.5 kgf/cm 2 ) High 1.37 to 1.57 MPa (14 to 16 kgf/cm 2 ) The A/C system periodically changes between normal and improper function due to moisture in the refrigerant system. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions During operation, pressure on low pressure side cycles between normal and vacuum Moisture in refrigeration system freezes at expansion valve orifice, causing temporary stop of cycle. However, when melted, normal state is restored. Drier is overly saturated Moisture in refrigeration system freezes at expansion valve orifice and blocks refrigerant circulation Replace cooler drier Remove moisture from cycle by repeatedly evacuating air Supply appropriate volume of new refrigerant The A/C system does not function effectively due to insufficient cooling. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions Pressure low on both low and high pressure sides Cooling performance insufficient Gas leakage from refrigeration system Insufficient refrigerant Refrigerant leakage Check for gas leakage and repair if necessary Supply appropriate volume of new refrigerant If indicated pressure value close to 0 when connected to gauge, create vacuum after inspecting and repairing the location of leakage The A/C system does not function effectively due to poor circulation of the refrigerant. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions Pressure low on both low and high pressure sides Frost exists on piping from condenser to A/C unit Refrigerant flow obstructed by dirt in condenser Condenser clogged Replace condenser The A/C system does not function intermittently because the refrigerant does not circulate. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions Vacuum indicated on low pressure side, and extremely low pressure indicated on high pressure side Frost or condensation seen on piping on both sides of condenser or expansion valve Refrigerant flow obstructed by moisture or dirt in refrigeration system Refrigerant flow obstructed by gas leakage from expansion valve Refrigerant does not circulate Check expansion valve refrigerant Clean expansion valve by blowing air Replace condenser Evacuate air and charge appropriate volume of new refrigerant For gas leakage from expansion valve, replace expansion valve The A/C system does not function effectively due to overcharged refrigerant or insufficient cooling of the condenser. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions Pressure extremely high on both low and high-pressure sides Excessive refrigerant Cooling performance of condenser insufficient Condenser is dirty Condenser fan motor is malfunctioning Excessive refrigerant Clean condenser Check condenser fan motor operation If 1 and 2 normal, check the amount of refrigerant and supply appropriate volume of refrigerant The A/C system does not function due to air in the refrigeration system. CAUTION: The low-pressure piping may be very hot and cause serious burns. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions Pressure extremely high on both low and high-pressure sides Low-pressure piping is too hot to touch Air in refrigeration system Air in refrigeration system Vacuum purging insufficient Check if compressor oil is dirty or insufficient Evacuate air and charge new refrigerant The A/C system does not function effectively due to an expansion valve malfunction. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions Pressure extremely high on both low and high-pressure sides Frost or condensation on piping on low-pressure side Problem with expansion valve Excessive refrigerant in low pressure piping Expansion valve too wide open Replace expansion valve The A/C system does not function due to a defective compressor. PROBLEM SYMPTOM CHART Symptoms Probable Cause Diagnosis Corrective Actions Pressure extremely high on both low and high-pressure sides Pressure extremely low on high pressure side Internal leakage in compressor Compression failure Leakage from damaged valve or broken sliding parts Repair or replace compressor

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1. DISCHARGE REFRIGERANT FROM REFRIGERATION SYSTEM Start up the engine. Turn the A/C switch ON. Operate the cooler compressor with an engine speed of approximately 1,000 RPM for 5 to 6 minutes to circulate the refrigerant and collect the compressor oil remaining in each component into the cooler compressor. Stop the engine. Using SST, discharge the refrigerant gas. SST 07110-58060 (07117-58060, 07117-58070, 07117-58080, 07117-58090, 07117-78050, 07117-88060, 07117-88070, 07117-88080)
2. CHARGE REFRIGERANT Perform vacuum purging using a vacuum pump. Charge refrigerant HFC-134a (R134a). Standard: 430 +-30 g (15.2 +-1.1 oz.) SST 07110-58060 (07117-58060, 07117-58070, 07117-58080, 07117-58090, 07117-78050, 07117-88060, 07117-88070, 07117-88080) NOTE: Do not operate the cooler compressor before charging refrigerant as the cooler compressor will not work properly without any refrigerant, and will overheat. Approximately 100 g (3.53 oz.) of refrigerant may need to be charged after bubbles disappear. The refrigerant amount should be checked by measuring its quantity, and not with the sight glass.
3. WARM UP ENGINE Warm up the engine at less than 1,850 RPM for 2 minutes or more after charging the refrigerant. NOTE: Be sure to warm up the compressor when turning the A/C switch ON after removing and installing the cooler refrigerant lines (including the compressor), to prevent damage to the compressor.
4. CHECK FOR LEAKAGE OF REFRIGERANT After recharging the refrigerant gas, check for refrigerant gas leakage using a halogen leak detector. Perform the operation under these conditions: Stop the engine. Secure good ventilation (the gas leak detector may react to volatile gases other than refrigerant, such as evaporated gasoline or exhaust gas). Repeat the test 2 or 3 times. Make sure that some refrigerant remains in the refrigeration system. When compressor is off: approximately 392 to 588 kPa (4 to 6 kgf/cm 2 , 57 to 85 psi) Using a gas leak detector, check the refrigerant line for leakage. If a gas leak is not detected on the drain hose, remove the blower motor control (blower resistor) from the cooling unit. Insert the gas leak detector sensor into the unit and perform the test. Disconnect the connector and leave the pressure switch on for approximately 20 minutes. Bring the gas leak detector close to the pressure switch and perform the test.

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1. DISCHARGE REFRIGERANT FROM REFRIGERATION SYSTEM (See «REPLACEMENT»(ref-265087-S42514689952007092000000) )
2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
3. REMOVE TUBE SUB-ASSEMBLY Remove the bolt. Remove plate, as shown. Disconnect the suction tube and liquid tube. NOTE: Do not use a screwdriver or similar tool to disconnect the tube. Seal the opening of the disconnected parts using vinyl tape to prevent moisture and foreign matter from entering them. Remove the 2 O-rings from the suction tube and liquid tube.
4. DISCONNECT INLET HEATER WATER HOSE Using pliers, grip the claws of the clip and slide the clip. Disconnect the heater water inlet hose.
5. DISCONNECT OUTLET HEATER WATER HOSE HINT: Disconnection of the heater water outlet hose is the same as for the heater water inlet hose.
6. REMOVE STEERING COLUMN ASSEMBLY Remove the steering column (see «REMOVAL»(ref-265052-S17500591692007092000000) ).
7. REMOVE UPPER INSTRUMENT PANEL Remove the upper instrument panel (see REMOVAL under «UPPER INSTRUMENT PANEL»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
8. REMOVE LOWER INSTRUMENT PANEL Remove the lower instrument panel (see REMOVAL under «LOWER INSTRUMENT PANEL»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
9. REMOVE DEFROSTER NOZZLE ASSEMBLY Detach the 3 claws and remove the defroster nozzle assembly.
10. REMOVE NO. 1 INSTRUMENT PANEL BRACE SUBASSEMBLY Fold the floor carpet back. Disconnect the clamp and disconnect the wire harness. Remove the bolt, nut, screw, and instrument panel brace.
11. REMOVE AIR DUCT REAR Disconnect the 2 clamps and disconnect the wire harness. Detach the 3 claws and remove the air duct rear.
12. REMOVE AIR DUCT Detach the 2 claws and remove the air duct.
13. REMOVE AIR CONDITIONING AMPLIFIER ASSEMBLY Detach the 2 clamps. Disconnect the connector. Remove the screw and amplifier.
14. REMOVE DRAIN COOLER HOSE Remove the drain hose.
15. REMOVE INSTRUMENT PANEL REINFORCEMENT Disconnect the 12 clamps. Remove the 4 bolts and disconnect the ground wire. Remove the 3 bolts. Remove the 6 bolts and instrument panel reinforcement.
16. REMOVE AIR CONDITIONER UNIT ASSEMBLY Remove the bolt, nut and A/C unit.

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1. REMOVE NO. 3 HEATER TO REGISTER DUCT Detach the 6 claws and remove the heater to register duct.
2. REMOVE AIR DUCT Detach the 2 claws and remove the air duct.
3. REMOVE AIR OUTLET CONTROL SERVO MOTOR Remove the 3 screws. Detach the evaporator case from the blower case. Remove the 3 screws and disconnect the connector. Remove the air outlet control servo motor.
4. REMOVE AIR MIX CONTROL SERVO MOTOR Remove the 3 screws and disconnect the connector. Remove the air mix control servo motor.
5. REMOVE MODE CONTROL CABLE ASSEMBLY (For Manual Air Conditioning System) Remove the 3 screws. Detach the evaporator case from the blower case. Detach the 3 claws and remove the cable.
6. REPAIR AIRMIX DAMPER CONTROL CABLE SUBASSEMBLY (For Manual Air Conditioning System) Detach the 3 claws and remove the cable.
7. REMOVE HEATER RADIATOR UNIT SUB-ASSEMBLY Detach the screw and remove the clamp. Remove the heater radiator unit.
8. REMOVE COOLER EXPANSION VALVE Using a 4 mm hexagon wrench, remove the 2 hexagon bolts. Remove the cooler expansion valve and 2 O-rings from the cooler evaporator.
9. REMOVE NO. 1 COOLER EVAPORATOR SUBASSEMBLY Remove the 4 screws. Detach the 2 claws and remove the cover. Detach the cooler thermistor clamp. Remove the cooler thermistor and cooler evaporator from the case.
10. REMOVE EVAPORATOR TEMPERATURE SENSOR Disconnect the cooler thermistor clamp from the cooler evaporator.

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1. INSTALL EVAPORATOR TEMPERATURE SENSOR NOTE: If reusing the evaporator, do not insert the sensor to a location where the sensor was previously inserted. Insert the sensor within range C shown in the illustration. Install the evaporator temperature sensor as shown in the illustration.
2. INSTALL NO. 1 COOLER EVAPORATOR SUBASSEMBLY Install the cooler thermistor and cooler evaporator on the case. Attach the temperature sensor clamp. Attach the 2 claws to install the cover. Install the 4 screws.
3. INSTALL COOLER EXPANSION VALVE Sufficiently apply compressor oil to 2 new O-rings and the fitting surface of the hose joint. Compressor oil: ND-OIL 8 or equivalent Install the 2 O-rings to the cooler evaporator. Install the cooler expansion valve. Using a 4 mm hexagon wrench, install the A/C tube with the 2 hexagon bolts. Torque: 3.5 N*m (35 kgf*cm, 30 in.*lbf)
4. INSTALL HEATER RADIATOR UNIT SUB-ASSEMBLY Install the heater radiator with the clamp and screw.
5. INSTALL AIRMIX DAMPER CONTROL CABLE SUBASSEMBLY (For Manual Air Conditioning System) Attach the 3 claws to install the cable.
6. INSTALL MODE CONTROL CABLE ASSEMBLY (For Manual Air Conditioning System) Attach the 3 claws to install the cable. Attach the evaporator case to the blower case. Install the cable with the 3 screws.
7. INSTALL AIR MIX CONTROL SERVO MOTOR Install the air mix control servo motor with the 3 screws and connect the connector.
8. INSTALL AIR OUTLET CONTROL SERVO MOTOR Install the air outlet control servo motor with the 3 screws and connect the connector. Attach the evaporator case to the blower case. Install the 3 screws.
9. INSTALL AIR DUCT Attach the 2 claws and install the air duct.
10. INSTALL NO. 3 HEATER TO REGISTER DUCT Attach the 6 claws and install the heater to register duct.

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1. INSTALL AIR CONDITIONER UNIT ASSEMBLY Install the A/C unit with the bolt and nut. Torque: 9.8 N*m (100 kgf*cm, 7 ft.*lbf)
2. INSTALL INSTRUMENT PANEL REINFORCEMENT Install the instrument panel reinforcement with the 6 bolts. Torque: 20 N*m (204 kgf*cm, 15 ft.*lbf) Install the 3 bolts. Torque: 9.8 N*m (100 kgf*cm, 7 ft.*lbf) Install the 4 bolts and connect the ground wire. Attach the 12 clamps.
3. INSTALL DRAIN COOLER HOSE Install the drain hose.
4. INSTALL AIR CONDITIONING AMPLIFIER ASSEMBLY Install the A/C amplifier with the screw. Connect the connector. Attach the 2 clamps to the amplifier.
5. INSTALL AIR DUCT Attach the 2 claws and install the air duct.
6. INSTALL REAR AIR DUCT Attach the 3 claws and install the air duct rear. Attach the 2 clamps and install the wire harness.
7. INSTALL NO. 1 INSTRUMENT PANEL BRACE SUBASSEMBLY Install the instrument panel brace with the bolt, nut and screw. Install the clamp and connect the wire harness. Reposition the floor carpet.
8. INSTALL DEFROSTER NOZZLE ASSEMBLY Attach the 3 claws and install the defroster nozzle assembly lower.
9. INSTALL LOWER INSTRUMENT PANEL Install the lower instrument panel (see «INSTALLATION»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
10. INSTALL UPPER INSTRUMENT PANEL Install the upper instrument panel (see «INSTALLATION»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
11. INSTALL STEERING COLUMN ASSEMBLY Install the steering column (see «INSTALLATION»(ref-265052-S25791091542007092000000) ).
12. CONNECT HEATER WATER OUTLET HOSE Connect the water hose and attach the clip.
13. CONNECT HEATER WATER INLET HOSE HINT: Use the same procedures described for the water outlet hose.
14. CONNECT TUBE SUB-ASSEMBLY Remove the attached vinyl tape from the pipe. Sufficiently apply compressor oil to new 2 O-rings and the fitting surface of the suction tube and liquid tube. Compressor oil: ND-OIL 8 or equivalent Install the 2 O-rings on the suction tube and liquid tube. Connect the suction tube and liquid tube. HINT: After the connection, check that the claw of the piping clamp is engaged. Install the plate with the bolt. Torque: 9.8 N*m (100 kgf*cm, 7 ft.*lbf)
15. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
16. CHECK SRS WARNING LIGHT Check the SRS warning light (see «DIAGNOSIS SYSTEM»(ref-281539-S07592235132008031700000) ).
17. REPLACE ENGINE COOLANT Refer to the following procedures (see «COOLANT»(ref-265075-S04845719212007092000000) ).
18. CHARGE REFRIGERANT (See «REPLACEMENT»(ref-265087-S42514689952007092000000) )
19. WARM UP ENGINE (See «REPLACEMENT»(ref-265087-S42514689952007092000000) )
20. CHECK FOR ENGINE COOLANT LEAKS
21. CHECK FOR LEAKAGE OF REFRIGERANT (See «REPLACEMENT»(ref-265087-S42514689952007092000000) )

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1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
2. REMOVE UPPER INSTRUMENT PANEL Remove the upper instrument panel (see REMOVAL under «UPPER INSTRUMENT PANEL»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
3. REMOVE LOWER INSTRUMENT PANEL Remove the lower instrument panel (see REMOVAL under «LOWER INSTRUMENT PANEL»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
4. REMOVE AIR DUCT (See «REMOVAL»(ref-265087-S23722011562007092000000) )
5. REMOVE AIR CONDITIONING UNIT Remove the air conditioning unit (see «REMOVAL»(ref-265087-S23722011562007092000000) ).
6. REMOVE BLOWER ASSEMBLY Remove the 3 screws and blower.

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1. REMOVE HEATER TO REGISTER DUCT ASSEMBLY Detach the 7 claws and register duct.
2. REMOVE AIR FILTER CASE Detach the 2 claws and remove the air filter case. Remove the air filter.
3. REMOVE AIR INLET CONTROL SERVO MOTOR (For Manual Air Conditioning System) Remove the 3 screws and air inlet servo motor.
4. REMOVE AIR INLET CONTROL SERVO MOTOR (For Automatic Air Conditioning System) Detach the claws and lever. Remove the 3 screws and air inlet servo motor.
5. REMOVE BLOWER RESISTOR (For Manual Air Conditioning System) Remove the 2 screws and blower resistor.
6. REMOVE BLOWER MOTOR Remove the 3 screws and blower motor.

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1. INSTALL BLOWER MOTOR Install the blower motor with the 3 screws.
2. INSTALL BLOWER RESISTOR (For Manual Air Conditioning System) Install the blower resistor with the 2 screws.
3. INSTALL AIR INLET CONTROL SERVO MOTOR (For Automatic Air Conditioning System) Install the air inlet servo motor with the 3 screws. Attach the claw to install the lever.
4. INSTALL AIR INLET CONTROL SERVO MOTOR (For Manual Air Conditioning System) Install the air inlet servo motor with the 3 screws.
5. INSTALL AIR FILTER CASE Install the air filter. Attach the 2 claws to install the air filter case.
6. INSTALL HEATER TO REGISTER DUCT ASSEMBLY Attach the 7 claws to install the register duct.

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1. INSTALL BLOWER ASSEMBLY Install the blower assembly with the 3 screws.
2. INSTALL AIR CONDITIONING UNIT Install the air conditioning unit (see «INSTALLATION»(ref-265087-S13942694552007092000000) ).
3. INSTALL AIR DUCT (See «INSTALLATION»(ref-265087-S13942694552007092000000) )
4. INSTALL LOWER INSTRUMENT PANEL Install the lower instrument panel (see «INSTALLATION»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
5. INSTALL UPPER INSTRUMENT PANEL Install the upper instrument panel (see «REASSEMBLY»(/toyota/rav4/iii-2005-2010/remont/gauges-instrument-panels/#instrument-panel) ).
6. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
7. CHECK SRS WARNING LIGHT Check the SRS warning light (see «DIAGNOSIS SYSTEM»(ref-281539-S07592235132008031700000) ).

1. Disconnect the blower motor connector.
2. Connect the positive (+) lead from the battery to terminal 1 and negative (-) lead to terminal 2, and then check that the motor operates smoothly. If the operation is not as specified, replace the blower motor.

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1. Disconnect the blower motor connector.
2. Connect the positive (+) lead from the battery to terminal 2 and negative (-) lead to terminal 1, and then check that the motor operates smoothly. If the operation is not as specified, replace the blower motor.

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1. INSPECT BLOWER MOTOR CONTROL Measure the resistance of the blower resistor. Standard resistance TERMINALS RESISTANCE SPECIFICATION Tester Connection Specified Condition 1 - 2 1.45 to 1.67 1 - 3 0.52 to 0.60 1 - 4 3.12 to 3.60 If the resistance is not as specified, replace the blower motor control.

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See also:
• ENGINE CONTROL SYSTEM (2AZ-FE) -- RAV4
• ENGINE CONTROL SYSTEM (2GR-FE) -- RAV4
• UPPER INSTRUMENT PANEL
• ON-VEHICLE INSPECTION