Air Conditioning (Diagnostic Codes & Circuit Tests): Overview Lexus IS II facelift

Scheme 16

Scheme 17

Scheme 18

1. ACTUATOR CHECK Start the engine and warm it up. Perform the indicator check. Refer to «CHECK MODE PROCEDURE»(ref-387433-S28003297002011022400000) . Push the "R/F" switch to perform the actuator check. HINT: Be sure to perform the actuator check after starting the engine. As the actuator check is repeated from steps 1 to 10 at 1 second intervals, check the temperature and air flow visually and by hand. HINT: The display blinks at 1 second intervals in the step operation. As an example, the illustration shows that display code 21 is output. Push the "OFF" switch to finish panel diagnosis. Push the "AUTO" switch to enter the sensor check mode. Step No. Display Code Conditions Blower Level Air Mix Damper Airflow Vent Air Inlet Damper Cool Air By-pass Damper Compressor 1 0 0 0% open FACE FRESH -14% OFF 2 1 1 0% open FACE FRESH -14% OFF 3 2 17 0% open FACE RECIRCULATION / FRESH -14% ON 4 3 17 0% open FACE RECIRCULATION 113.50% ON 5 4 17 50% open B/L RECIRCULATION 113.50% ON 6 5 17 50% open B/L RECIRCULATION 113.50% ON 7 6 17 50% open FOOT FRESH 113.50% ON 8 7 17 100% open FOOT-0 FRESH 113.50% ON 9 8 17 100% open F/D FRESH 113.50% ON 10 9 31 100% open DEF FRESH 113.50% ON If the steps are difficult to read because they change automatically, push the "UPDr" switch to display the steps one at a time so that they can be read easily. The items are displayed step by step each time the "UPDr" switch is pushed. HINT: Push the "OFF" switch to finish panel diagnosis. Push the "R/F" switch to enter the sensor check mode.

DESCRIPTION

This sensor detects the cabin temperature that is used as the basis for temperature control and sends a signal to the A/C amplifier.

Scheme 19

Scheme 20

Scheme 21

Scheme 22

1. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Select the item below in the Data List, and read the display on the Techstream. DATA LIST / AIR CONDITIONER: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Room Temperature Sensor (Room Temp) Room temperature sensor / min.: -6.5°C (20.3°F), max.: 57.25°C (135.05°F) Actual cabin temperature is displayed - OK The display is as specified in the normal condition column. Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOM TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE AIR CONDITIONING AMPLIFIER B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) A: Go to next step
2. INSPECT AIR CONDITIONING AMPLIFIER Remove the A/C amplifier with the connectors still connected. Turn the engine switch on (IG). Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Condition Specified Condition J58-16 (TR) - J58-19 (SG-1) Engine switch on (IG) at 25°C (77°F) 1.8 to 2.2 V J58-16 (TR) - J58-19 (SG-1) Engine switch on (IG) at 40°C (104°F) 1.2 to 1.6 V HINT: As the temperature increases, the voltage decreases. Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOM TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE AIR CONDITIONING AMPLIFIER B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) PROBLEM SYMPTOMS TABLE A: Go to next step
3. INSPECT A/C ROOM TEMPERATURE SENSOR Remove the A/C room temperature sensor. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition J38-1 - J38-2 10°C (50°F) 3.00 to 3.73 kohms J38-1 - J38-2 15°C (59°F) 2.45 to 2.88 kohms J38-1 - J38-2 20°C (68°F) 1.95 to 2.30 kohms J38-1 - J38-2 25°C (77°F) 1.60 to 1.80 kohms J38-1 - J38-2 30°C (86°F) 1.28 to 1.47 kohms J38-1 - J38-2 35°C (95°F) 1.00 to 1.22 kohms J38-1 - J38-2 40°C (104°F) 0.80 to 1.00 kohms J38-1 - J38-2 45°C (113°F) 0.65 to 0.85 kohms J38-1 - J38-2 50°C (122°F) 0.50 to 0.70 kohms J38-1 - J38-2 55°C (131°F) 0.44 to 0.60 kohms J38-1 - J38-2 60°C (140°F) 0.36 to 0.50 kohms NOTE: Hold the sensor only by its connector. Touching the sensor may change the resistance value. When measuring, the sensor temperature must be the same as the ambient temperature. HINT: As the temperature increases, the resistance decreases (Scheme 21) NG --> REPLACE A/C ROOM TEMPERATURE SENSOR OK: Go to next step
4. CHECK HARNESS AND CONNECTOR (A/C ROOM TEMPERATURE SENSOR - AIR CONDITIONING AMPLIFIER) Disconnect the connectors from the A/C room temperature sensor and A/C amplifier. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition J58-16 (TR) - J38-1 Always Below 1 ohms J58-19 (SG-1) - J38-2 Always Below 1 ohms J58-16 (TR) - Body ground Always 10 kohms or higher J58-19 (SG-1) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE AIR CONDITIONING AMPLIFIER

The ambient temperature sensor is installed in front of the condenser to detect the ambient temperature which is used to control the air conditioner "AUTO" mode. This sensor connected to the ECM and detects fluctuations in the ambient temperature. This data is used for controlling the cabin temperature. The sensor sends a signal to the A/C amplifier via the ECM. 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 ECM applies voltage (5 V) to the ambient temperature sensor and reads voltage changes as the resistance of the ambient temperature sensor changes. The ECM sends the signal to the A/C amplifier via CAN and body multiplex communication.

Scheme 23

Scheme 24

Scheme 25

1. CHECK MULTIPLEX COMMUNICATION SYSTEM Use the Techstream to check if the Multiplex Communication System (MPX) is functioning normally. Result Result Proceed to MPX DTC is not output A MPX DTC is output B B --> GO TO MULTIPLEX COMMUNICATION SYSTEM A: Go to next step
2. CHECK CAN COMMUNICATION SYSTEM Use the Techstream to check if the CAN Communication System is functioning normally. Result Result Proceed to CAN DTC is not output A CAN DTC is output B B --> GO TO CAN COMMUNICATION SYSTEM A: Go to next step
3. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Select the item below in the Data List, and read the display on the Techstream. DATA LIST / AIR CONDITIONER: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Ambient Temp Sensor (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 in circuit: -23.3°C (-9.94°F) Short in circuit: 65.95°C (150.71°F) OK The display is as specified in the normal condition column. Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE AIR CONDITIONING AMPLIFIER B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) A: Go to next step
4. INSPECT AMBIENT TEMPERATURE SENSOR Remove the ambient temperature sensor. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition B5-1 - B5-2 10°C (50°F) 3.00 to 3.73 kohms B5-1 - B5-2 15°C (59°F) 2.45 to 2.88 kohms B5-1 - B5-2 20°C (68°F) 1.95 to 2.30 kohms B5-1 - B5-2 25°C (77°F) 1.60 to 1.80 kohms B5-1 - B5-2 30°C (86°F) 1.28 to 1.47 kohms B5-1 - B5-2 35°C (95°F) 1.00 to 1.22 kohms B5-1 - B5-2 40°C (104°F) 0.80 to 1.00 kohms B5-1 - B5-2 45°C (113°F) 0.65 to 0.85 kohms B5-1 - B5-2 50°C (122°F) 0.50 to 0.70 kohms B5-1 - B5-2 55°C (131°F) 0.44 to 0.60 kohms B5-1 - B5-2 60°C (140°F) 0.36 to 0.50 kohms NOTE: Even slightly touching the sensor 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 24) NG --> REPLACE AMBIENT TEMPERATURE SENSOR OK: Go to next step
5. CHECK WIRE HARNESS (AMBIENT TEMPERATURE SENSOR - ECM) Disconnect the ambient temperature sensor connector. Disconnect the ECM connectors. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition B5-1 - A5-18 (TAM) (*1) Always Below 1 ohms B5-2 - E5-30 (E3) (*1) Always Below 1 ohms B5-1 - A5-26 (TAM) (*2) Always Below 1 ohms B5-2 - E5-27 (ETAM) (*2) Always Below 1 ohms A5-18 (TAM) - Body ground (*1) Always 10 kohms or higher E5-30 (E3) - Body ground (*1) Always 10 kohms or higher A5-26 (TAM) - Body ground (*2) Always 10 kohms or higher A5-27 (ETAM) - Body ground (*2) Always 10 kohms or higher *1: for 4GR-FSE *2: for 2GR-FSE NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE ECM

The evaporator temperature sensor (A/C thermistor) is installed on the evaporator in the air conditioner unit. It detects the temperature of the cooled air that has passed through the evaporator and its signal is used to control the air conditioning. It sends a signal to the A/C amplifier. The resistance of the evaporator temperature sensor (A/C thermistor) changes in accordance with the temperature of the cooled air that has passed through the evaporator. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The A/C amplifier applies voltage (5 V) to the evaporator temperature sensor (A/C thermistor) and reads voltage changes as the resistance of the evaporator temperature sensor (A/C thermistor) changes. This sensor is used to prevent the evaporator from freezing.

Scheme 26

Scheme 27

1. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Select the item below in the Data List, and read the display on the Techstream. DATA LIST / AIR CONDITIONER: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Evaporator Temp Sensor (Evap Temp) Evaporator temperature sensor / Min.: -29.7°C (-21.46°F), Max.: 59.55°C (139.19°F) Actual evaporator temperature is displayed Open in circuit: -29.7°C (-21.46°F) Short in circuit: 59.55°C (139.19°F) OK The display is as specified in the normal condition column. Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE AIR CONDITIONING AMPLIFIER B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) A: Go to next step
2. INSPECT AIR CONDITIONING HARNESS Remove the air conditioning harness (evaporator temperature sensor). Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition e1-5 - e1-6 -10°C (14°F) 7.30 to 9.10 kohms e1-5 - e1-6 -5°C (23°F) 5.65 to 6.95 kohms e1-5 - e1-6 0°C (32°F) 4.40 to 5.35 kohms e1-5 - e1-6 5°C (41°F) 3.40 to 4.15 kohms e1-5 - e1-6 10°C (50°F) 2.70 to 3.25 kohms e1-5 - e1-6 15°C (59°F) 2.14 to 2.58 kohms e1-5 - e1-6 20°C (68°F) 1.71 to 2.05 kohms e1-5 - e1-6 25°C (77°F) 1.38 to 1.64 kohms e1-5 - e1-6 30°C (86°F) 1.11 to 1.32 kohms NOTE: Even slightly touching the sensor 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 27) NG --> REPLACE AIR CONDITIONING HARNESS OK --> REPLACE AIR CONDITIONING AMPLIFIER

The smog ventilation sensor, which is installed on the front of the condenser, is used for automatic air inlet control. This sensor detects CO and HC in the emission gas and transmits signals to the A/C amplifier.

Scheme 28

Scheme 29

Scheme 30

Scheme 31

Scheme 32

1. INSPECT FUSE (LH-IG) Remove the LH-IG fuse from the cowl side junction block LH. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Item Condition Specified Condition LH-IG fuse Always Below 1 ohms NG --> REPLACE FUSE (LH-IG) OK: Go to next step
2. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Allow exhaust gas (HC, CO) to travel to the sensing portion of the smog ventilation sensor. Select the item below in the Data List, and read the display on the Techstream. DATA LIST / AIR CONDITIONER: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Emission Gas Sensor (Emiss Gas Sens) Emission gas / Min.: 0 V, Max.: 255 V Smog ventilation sensor value increases as gas amount increases - OK The display is as specified in the normal condition column. Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE AIR CONDITIONING AMPLIFIER B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) A: Go to next step
3. CHECK WIRE HARNESS (SMOG VENTILATION SENSOR - BODY GROUND) Disconnect the smog ventilation sensor connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition B11-6 (E) - Body ground Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
4. CHECK WIRE HARNESS (SMOG VENTILATION SENSOR - BATTERY) Disconnect the smog ventilation sensor connector. Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Condition Specified Condition B11-3 (IG) - Body ground Engine switch on (IG) 10 to 14 V Engine switch off Below 1 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
5. INSPECT SMOG VENTILATION SENSOR Remove the smog ventilation sensor. Apply battery voltage between terminals 3 (IG) and 6 (E). Allow exhaust gas (HC, CO) to travel to the sensing portion of the smog ventilation sensor, and measure the resistance between terminals 1 (SG) and 2 (DGS). OK When the sensor is exposed to the exhaust gas, the resistance increases. HINT: The resistance before blowing exhaust gas is 10 kohms to 40 kohms. NG --> REPLACE SMOG VENTILATION SENSOR OK: Go to next step
6. CHECK WIRE HARNESS (SMOG VENTILATION SENSOR - A/C AMPLIFIER) Disconnect the smog ventilation sensor. Disconnect the A/C amplifier connector. Measure the resistance of the wire harness side connectors. Standard resistance Tester Connection Condition Specified Condition B11-1 (SG) - J58-39 (SG-6) Always Below 1 ohms B11-2 (DGS) - J58-34 (DGS) Always Below 1 ohms J58-39 (SG-6) - Body ground Always 10 kohms or higher J58-34 (DGS) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE AIR CONDITIONING AMPLIFIER

Scheme 33

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

Scheme 34

This sensor sends 1 pulse per engine revolution to the ECM.

If the ratio between engine and compressor speed deviates 20% or more compared to normal operation, the ECM turns the cooler compressor off and the indicator blinks at approximately 1 second intervals.

The ECM informs the A/C amplifier of the operation condition of the cooler compressor through multiplex communication (CAN and BEAN).

Scheme 35

Scheme 36

Scheme 37

Scheme 38

1. CHECK MULTIPLEX COMMUNICATION SYSTEM Use the Techstream to check if the Multiplex Communication System (MPX) is functioning normally. Result Result Proceed to MPX DTC is not output A MPX DTC is output B B --> GO TO MULTIPLEX COMMUNICATION SYSTEM A: Go to next step
2. CHECK CAN COMMUNICATION SYSTEM Use the Techstream to check if the CAN Communication System is functioning normally. Result Result Proceed to CAN DTC is not output A CAN DTC is output B B --> GO TO CAN COMMUNICATION SYSTEM A: Go to next step
3. INSPECT ECM Remove the ECM with its connectors still connected. Measure the waveform of the connector. Standard Tester Connection Condition Specified Condition E3-10 (LCKI) - Body ground Engine switch on (IG) AUTO switch ON A/C switch ON Magnetic clutch ON Pulse generation Item Contents Tool setting 200 mV/DIV., 10 ms/DIV. Vehicle condition Engine switch on (IG) AUTO switch ON A/C switch ON Magnetic clutch ON Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE ECM B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) A: Go to next step
4. INSPECT A/C COMPRESSOR (LOCK SENSOR) Disconnect the A/C compressor connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition E8-2 (SSR+) - E8-5 (SSR-) 160 to 320 ohms NG --> REPLACE A/C COMPRESSOR (LOCK SENSOR) OK: Go to next step
5. CHECK WIRE HARNESS (ECM - A/C COMPRESSOR) Disconnect the A/C compressor connector. Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition E3-10 (LCKI) - E8-2 (SSR+) Always Below 1 ohms E3-10 (LCKI) - Body ground Always 10 kohms or higher E8-5 (SSR-) - Body ground Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE ECM

This DTC is output when refrigerant pressure is 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 pressure sensor, which is installed on the pipe of the high pressure side to detect refrigerant pressure, outputs a refrigerant pressure signal to the A/C amplifier. The A/C amplifier converts this signal to pressure according to the sensor characteristics to control the compressor.

HINT

Be sure to check the refrigerant volume first when this DTC is output because this DTC can also be output if there is no refrigerant in the system.

Scheme 39

Scheme 40

Scheme 41

Scheme 42

1. CHECK REFRIGERANT Check the sight glass of the cooler unit refrigerant liquid pipe. Prepare the vehicle according to the chart below. Item Condition Vehicle Doors Fully open Temperature Setting MAX COLD Blower Speed HI A/C ON Compare the sight glass to the following chart. Item Symptom Amount of Refrigerant Corrective Actions 1 Bubbles visible Insufficient* Check for gas leakage and repair if necessary Add refrigerant until bubbles disappear 2 No bubbles visible Empty, insufficient, or excessive Refer to 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 Evacuate A/C system and recharge with proper amount of refrigerant 4 Considerable temperature difference between compressor inlet and outlet Proper or excessive Refer to 5 and 6 5 Immediately after air conditioning is turned OFF, refrigerant clears Excessive Recover refrigerant Evacuate A/C system and recharge with proper amount of refrigerant 6 Immediately after air conditioning is turned OFF, refrigerant foams and then becomes clear Proper - * : Bubbles in the sight glass with the vehicle interior temperature above 35°C (95°F) can be considered normal if cooling is sufficient. NG --> CHARGE REFRIGERANT OK: Go to next step
2. CHECK WIRE HARNESS (PRESSURE SENSOR - A/C AMPLIFIER) Disconnect the pressure sensor connector. Disconnect the A/C amplifier connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition B7-2 (PR) - J58-13 (PRE) Always Below 1 ohms B7-3 (+) - J58-26 (S5-2) Always Below 1 ohms B7-1 (-) - J58-38 (SG-2) Always Below 1 ohms J58-13 (PRE) - Body ground Always 10 kohms or higher J58-26 (S5-2) - Body ground Always 10 kohms or higher J58-38 (SG-2) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. INSPECT PRESSURE SENSOR Install the manifold gauge set. Refer to «ON-VEHICLE INSPECTION»(ref-387355-S17683925712011022400000) . Connect the three 1.5 V dry cell batterie's 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 according to refrigerant pressure, as shown in the graph. Result Result Proceed to NG A OK (When troubleshooting according to the DTC) B OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) C C --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) B --> REPLACE AIR CONDITIONING AMPLIFIER A --> REPLACE PRESSURE SENSOR

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

Scheme 43

The air mix damper servo sends pulse signals to inform the air conditioner amplifier of the damper position. The air conditioner amplifier activates the motor (normal, reverse) based on the signals to move the air mix damper (passenger seat) to any position, which adjusts the amount of air passing the heater core after passing the evaporator to control the blowing temperature.

HINT

Confirm that no mechanical problem is present because this diagnostic code can be output when either a damper link or damper is mechanically locked.

Scheme 44

The damper servo (air inlet control) sends pulse signals to inform the air conditioner amplifier of the damper position. The air conditioner amplifier activates the motor (normal, reverse) based on the signals to move the air inlet mode selection air inlet control damper to any position, which controls the intake air settings (FRESH, FRESH / RECIRCULATION, and RECIRCULATION).

HINT

Confirm that no mechanical problem is present because this diagnostic code can be output when either a damper link or damper is mechanically locked.

Scheme 45

The mode damper servo sends pulse signals to inform the air conditioner amplifier of the damper position. The air conditioner amplifier activates the motor (normal, reverse) based on the signals to move the mode damper to any position, which controls the air outlet switching.

HINT

Confirm that no mechanical problem is present because this diagnostic code can be output when either a damper link or damper is mechanically locked.

Scheme 46

The damper servo (cool air by-pass) sends pulse signals to inform the air conditioner amplifier of the damper position. The air conditioner amplifier activates the motor (normal, reverse) based on the signals to move the damper to any position. As a result, when the A/C is operating, the temperature of the air blowing toward the passenger's head area is controlled.

HINT

Confirm that no mechanical problem is present because this diagnostic code can be output when either a damper link or damper is mechanically locked.

Scheme 47

The air mix damper servo sends pulse signals to inform the air conditioner amplifier of the damper position. The air conditioner amplifier activates the motor (normal, reverse) based on the signals to move the air mix damper (driver seat) to any position. As a result, the amount of air passing through the heater core after passing through the evaporator is adjusted, and the temperature of the air blowing toward the driver seat side is controlled.

HINT

Confirm that no mechanical problem is present because this diagnostic code can be output when either a damper link or damper is mechanically locked.

Scheme 48

In this circuit, the compressor receives a refrigerant compression demand signal from the air conditioning amplifier.

Based on this signal, the compressor changes the amount of compressor output.

Scheme 49

Scheme 50

Scheme 51

Scheme 52

1. INSPECT A/C COMPRESSOR Disconnect the A/C compressor connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition E8-3 (SOL+) - E8-6 (SOL-) 20°C (68°F) 10 to 11 ohms NG --> REPLACE A/C COMPRESSOR OK: Go to next step
2. CHECK WIRE HARNESS (A/C COMPRESSOR - BODY GROUND) Disconnect the A/C compressor connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition E8-6 (SOL-) - Body ground Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. CHECK WIRE HARNESS (A/C COMPRESSOR - A/C AMPLIFIER) Disconnect the A/C compressor connector. Disconnect the A/C amplifier connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition J58-5 (SOL+) - E8-3 (SOL+) Always Below 1 ohms J58-5 (SOL+) - Body ground Always 10 kohms or higher Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE AIR CONDITIONING AMPLIFIER B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) A --> REPAIR OR REPLACE HARNESS OR CONNECTOR

The smog ventilation sensor detects NOx in the emission gas and transmits signals to the A/C amplifier. Based on the signals, the A/C amplifier performs automatic air inlet control (FRESH, FRESH / RECIRCULATION, or RECIRCULATION mode).

Scheme 53

Scheme 54

1. INSPECT FUSE (LH-IG) Remove the LH-IG fuse from the cowl side junction block LH. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Item Condition Specified Condition LH-IG fuse Always Below 1 ohms NG --> REPLACE FUSE (LH-IG) OK: Go to next step
2. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Allow exhaust gas (NOx) to travel to the sensing portion of the smog ventilation sensor. Select the item below in the Data List, and read the display on the Techstream. DATA LIST / AIR CONDITIONER: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Emission Gas Nox Sensor (Nox Gas Sens) Emission gas NOx sensor / Min.: 0, Max.: 255 Smog ventilation sensor value increases as gas amount increases - OK The display is as specified in the normal condition column. Result Result Proceed to NG A OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B OK (When troubleshooting according to the DTC) C C --> REPLACE AIR CONDITIONING AMPLIFIER B --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) A: Go to next step
3. CHECK WIRE HARNESS (SMOG VENTILATION SENSOR - BODY GROUND) Disconnect the smog ventilation sensor connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition B11-6 (E) - Body ground Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
4. CHECK WIRE HARNESS (SMOG VENTILATION SENSOR - BATTERY) Disconnect the smog ventilation sensor connector. Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Condition Specified Condition B11-3 (IG) - Body ground Engine switch on (IG) 10 to 14 V Engine switch off Below 1 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
5. INSPECT SMOG VENTILATION SENSOR Remove the smog ventilation sensor. Apply battery voltage between terminals 3 (IG) and 6 (E). Allow exhaust gas (NOx) to travel to the sensing portion of the smog ventilation sensor, and measure the resistance between terminals 1 (SG) and 4 (DGS1). OK When the sensor is exposed to the exhaust gas, the resistance increases. HINT: The resistance before blowing exhaust gas is 10 kohms to 40 kohms. NG --> REPLACE SMOG VENTILATION SENSOR OK: Go to next step
6. CHECK WIRE HARNESS (SMOG VENTILATION SENSOR - A/C AMPLIFIER) Disconnect the exhaust gas sensor connector. Disconnect the A/C amplifier connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition B11-1 (SG) - J58-39 (SG-6) Always Below 1 ohms B11-4 (DGS1) - J58-33 (DGS1) Always Below 1 ohms J58-39 (SG-6) - Body ground Always 10 kohms or higher J58-33 (DGS1) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE AIR CONDITIONING AMPLIFIER

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

Scheme 55

Scheme 56

Scheme 57

Scheme 58

1. CHECK HARNESS AND CONNECTOR Remove the A/C amplifier. Disconnect the connector from the A/C amplifier. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition J58-20 (GND) - Body ground Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
2. CHECK AIR CONDITIONING AMPLIFIER Reconnect the connector to the A/C amplifier. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition e1-2 (BUS G) - J58-20 (GND) Always Below 1 ohms NG --> REPLACE AIR CONDITIONING AMPLIFIER OK: Go to next step
3. CHECK AIR CONDITIONING AMPLIFIER Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Condition Specified Condition e1-4 (B BUS) - e1-2 (BUS G) Engine switch off Below 1 V e1-4 (B BUS) - e1-2 (BUS G) Engine switch on (IG) 10 to 14 V NG --> REPLACE AIR CONDITIONING AMPLIFIER OK --> REPLACE AIR CONDITIONING HARNESS

The A/C amplifier sends a magnetic clutch ON command signal to the ECM through the BEAN line and CAN line. Then the ECM turns the A/C COMP relay on to turn the magnetic clutch on.

Scheme 59

Scheme 60

Scheme 61

Scheme 62

Scheme 63

Scheme 64

Scheme 65

1. CHECK MULTIPLEX COMMUNICATION SYSTEM Use the Techstream to check if the Multiplex Communication System (MPX) is functioning normally. Result Result Proceed to MPX DTC is not output A MPX DTC is output B B --> GO TO MULTIPLEX COMMUNICATION SYSTEM A: Go to next step
2. CHECK CAN COMMUNICATION SYSTEM Use the Techstream to check if the CAN Communication System is functioning normally. Result Result Proceed to CAN DTC is not output A CAN DTC is output B B --> GO TO CAN COMMUNICATION SYSTEM A: Go to next step
3. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Turn the A/C switch on and off. Select the item below in the Data List, and read the display on the Techstream. DATA LIST / ENGINE AND ECT: Tester Display Measurement Item/Range Normal Condition Diagnostic Note A/C Signal (A/C Signal) A/C signal / ON or OFF ON: A/C ON OFF: A/C OFF - OK The display is as specified in the normal condition column. NG --> See step 12 OK: Go to next step
4. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Change the blower fan speed to LO using the blower switch. Turn the A/C switch on and off. Select the item below in the Data List, and read the display on the Techstream. DATA LIST / ENGINE AND ECT: Tester Display Measurement Item/Range Normal Condition Diagnostic Note A/C Magnetic Clutch Relay (A/C Mag Clutch) A/C magnetic clutch relay / OFF, ON ON: A/C magnetic clutch ON OFF: A/C magnetic clutch OFF - OK The display is as specified in the normal condition. NG --> REPLACE ECM OK: Go to next step
5. PERFORM ACTIVE TEST USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Select the item below in the Active Test and read the display on the Techstream. ACTIVE TEST / ENGINE AND ECT: Tester Display Test Part Control Range Diagnostic Note Control the A/C Magnet Clutch (A/C Magnet Clutch) Magnetic Clutch Relay OFF, ON - OK The magnetic clutch operates normally. OK --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000) NG: Go to next step
6. INSPECT FUSE (A/C COMP) Remove the A/C COMP fuse from the engine room R/B and J/B No. 2. Measure the resistance of the fuse. Standard resistance Tester Item Condition Specified Condition A/C COMP fuse Always Below 1 ohms NG --> REPLACE FUSE (A/C COMP) OK: Go to next step
7. INSPECT RELAY (A/C COMP) Remove the A/C COMP relay from the engine room R/B and J/B No. 2. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Specified Condition 3 - 5 10 kohms or higher 3 - 5 Below 1 ohms (when battery voltage is applied to terminals 1 and 2) NG --> REPLACE RELAY (A/C COMP) OK: Go to next step
8. INSPECT A/C COMPRESSOR Disconnect the A/C compressor connector. Disconnect the magnetic clutch connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition E8-1 (MG+) - A-1 Always Below 1 ohms E8-1 (MG+) - Body ground Always 10 kohms or higher NG --> REPLACE A/C COMPRESSOR OK: Go to next step
9. INSPECT MAGNETIC CLUTCH Measure the resistance of the connector. Standard resistance Tester Connection Condition Specified Condition A-1 - Body ground Always 3.4 to 3.8 ohms When connector terminal A1 is connected to the positive (+) battery terminal, check that the following occurs: 1) the magnetic clutch's operating sound can be heard, and 2) the magnetic clutch's hub and rotor lock. NG --> REPLACE MAGNETIC CLUTCH OK: Go to next step
10. CHECK WIRE HARNESS (ENGINE ROOM R/B AND J/B NO. 2 - A/C COMPRESSOR) Turn the engine switch on (IG). Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Specified Condition Relay block A/C COMP relay terminal 5 - Body ground 10 to 14 V Relay block A/C COMP relay terminal 1 - Body ground 10 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
11. CHECK WIRE HARNESS (ENGINE ROOM R/B AND J/B NO. 2 - ECM) Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. Standard resistance 4GR-FSE Tester Connection Specified Condition Relay block A/C COMP relay terminal 2 - A6-13 (ACMG) Below 1 ohms A6-13 (ACMG) - Body ground 10 kohms or higher 2GR-FSE Tester Connection Specified Condition Relay block A/C COMP relay terminal 2 - A6-11 (ACMG) Below 1 ohms A6-11 (ACMG) - Body ground 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPAIR OR REPLACE HARNESS OR CONNECTOR (A/C COMPRESSOR - ENGINE ROOM R/B AND J/B NO. 2)
12. REPLACE AIR CONDITIONING AMPLIFIER Replace the A/C amplifier with a normal one and check that the condition returns to normal. OK Same problem does not occur. OK --> END NG --> REPLACE ECM

The GLW RLY turns on when it receives a signal from the A/C amplifier. As a result, power is supplied to the heater glow plug.

Scheme 66

Scheme 67

Scheme 68

Scheme 69

Scheme 70

Scheme 71

Scheme 72

Scheme 73

1. INSPECT FUSE (LH-IG, GLW PLG1, GLW PLG2) Remove the LH-IG fuse from the cowl side J/B LH. Remove the GLW PLG1 and GLW PLG2 fuses from the engine room R/B and J/B No. 1. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Item Condition Specified Condition LH-IG fuse Always Below 1 ohms GLW PLG1 fuse Always Below 1 ohms GLW PLG2 fuse Always Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
2. INSPECT RELAY (GLW RLY1, GLW RLY2) Remove the GLW RLY1 and GLW RLY2 relays from the engine room R/B and J/B No. 1. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Condition Specified Condition 3 - 5 Always 10 kohms or higher 3 - 5 When battery voltage is applied to terminals 1 and 2 Below 1 ohms NG --> REPLACE RELAY OK: Go to next step
3. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY) Disconnect the connector from the A/C amplifier. Turn the engine switch on (IG). Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection (Symbols) Condition Specified Condition J58-4 (HTR2) - Body ground Engine switch on (IG) 10 to 14 V J58-23 (HTR1) - Body ground Engine switch on (IG) 10 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
4. INSPECT AIR CONDITIONING AMPLIFIER Reconnect the connector to the A/C amplifier. Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Condition Specified Condition J58-4 (HTR2) - Body ground Engine switch on (IG) 10 to 14 V J58-4 (HTR2) - Body ground Engine switch on (IG) While the PTC operating conditions are met (engine is running at 850 rpm or more, ambient temperature is 0°C (32°F) or less, engine coolant temperature is 69°C (156°F) or less, and A/C switch setting is MAX HOT), turn the blower switch to the LO setting. Below 1 V J58-23 (HTR1) - Body ground Engine switch on (IG) 10 to 14 V D47-2 - Body ground Engine switch on (IG) While the PTC operating conditions are met (engine is running at 850 rpm or more, ambient temperature is 0°C (32°F) or less, engine coolant temperature is 69°C (156°F) or less, and A/C switch setting is MAX HOT), turn the blower switch to the LO setting. Below 1 V NG --> REPLACE AIR CONDITIONING AMPLIFIER OK: Go to next step
5. INSPECT HEATER BLOWER WIRE Remove the grommets and nuts of the water by-pass glow plugs. Turn the engine switch on (IG). Perform Active Test by referring to the table below. ACTIVE TEST / AIR CONDITIONER: Tester Display Test Part Control Range Diagnostic Note Electric Heater1 (Heater1) Electric Heater 1 OFF, ON - Electric Heater2 (Heater2) Electric Heater 2 OFF, ON - Measure the voltage according to the value(s) in the table below. Standard voltage Tester connection Condition Specified condition 1 - Body ground Perform ACTIVE TEST / HEATER 1 (Electric Heater 1): ON 10 to 14 V 2 - Body ground Perform ACTIVE TEST / HEATER 2 (Electric Heater 2): ON 10 to 14 V NG --> REPAIR OR REPLACE HEATER BLOWER WIRE OK: Go to next step
6. INSPECT WATER BY-PASS GLOW PLUG Remove the water by-pass glow plug. Measure the resistance according to the value(s) in the table below. Standard resistance Below 1 ohms NG --> REPLACE WATER BY-PASS GLOW PLUG OK --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000)

The low pressure sensor reduces the capacity of the compressor when the compressor is operating at high speed. This sensor monitors the pressure on the low pressure side at terminal CUT+ and sends a signal to terminal PSW of the A/C amplifier, which increases the accuracy of compressor control.

Scheme 74

Scheme 75

Scheme 76

1. CHECK REFRIGERANT PRESSURE Check the sight glass of the cooler unit refrigerant liquid pipe. Prepare the vehicle according to the chart below. Item Condition Vehicle Doors Fully open Temperature Setting MAX COLD Blower Speed HI A/C ON Compare the sight glass to the following chart. Item Symptom Amount of Refrigerant Corrective Actions 1 Bubbles visible Insufficient * Check for gas leakage and repair if necessary Add refrigerant until bubbles disappear 2 No bubbles visible Empty, insufficient, or excessive Refer to 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 Evacuate A/C system and recharge with proper amount of refrigerant 4 Considerable temperature difference between compressor inlet and outlet Proper or excessive Refer to 5 and 6 5 Immediately after air conditioning is turned OFF, refrigerant clears Excessive Recover refrigerant Evacuate A/C system and recharge with proper amount of refrigerant 6 Immediately after air conditioning is turned OFF, refrigerant foams and then becomes clear Proper - * : Bubbles in the sight glass with the vehicle interior temperature above 35°C (95°F) can be considered normal if cooling is sufficient. NG --> CHARGE REFRIGERANT OK: Go to next step
2. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - LOW PRESSURE SENSOR) Disconnect the pressure sensor connector. Disconnect the A/C amplifier connector. Measure the resistance according to the value(s) in the table below. Tester Connection (Symbols) Condition Specified Condition J58-18 (SG-3) - A56-1 (-S) Always Below 1 ohms J58-27 (S5-3) - A56-3 (+S) Always Below 1 ohms J58-32 (PSW) - A56-2 (CUT+) Always Below 1 ohms J58-18 (SG-3) - Body ground Always 10 kohms or higher J58-27 (S5-3) - Body ground Always 10 kohms or higher J58-32 (PSW) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. INSPECT LOW PRESSURE SENSOR Install the manifold gauge set. Refer to «ON-VEHICLE INSPECTION»(ref-387355-S17683925712011022400000) . Connect the three 1.5 V dry cell batterie's 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 according to refrigerant pressure, as shown in the graph. NG --> REPLACE LOW PRESSURE SENSOR OK --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000)

The main power source is supplied to the A/C amplifier when the engine switch on (IG).

The power source is used for operating the A/C amplifier and servo motor, etc.

Scheme 77

The back-up power source circuit for the A/C amplifier is shown below. Power is supplied even when turning the engine switch off and is used for diagnostic trouble code memory, etc.

Scheme 78

Scheme 79

Scheme 80

1. INSPECT FUSE (A/C) Remove the A/C fuse from the cowl side junction block LH. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Item Condition Specified Condition A/C fuse Always Below 1 ohms NG --> REPLACE FUSE (A/C) OK: Go to next step
2. INSPECT AIR CONDITIONING AMPLIFIER (AIR CONDITIONING AMPLIFIER - BODY GROUND) Disconnect the A/C amplifier connector. Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Condition Specified Condition J58-1 (B) - Body ground Always 10 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> PROCEED TO «PROBLEM SYMPTOMS TABLE»(ref-387433-S05197837142011022400000)