Reading and Clearing Diagnostic Trouble Codes
TROUBLE DIAGNOSIS
Self-Diagnosis Function
DESCRIPTION
The self-diagnosis system diagnoses sensors, door motors, blower motor, etc. by system line. Refer to applicable sections (items) for details. Shifting from normal control to the self-diagnosis system is accomplished by starting the engine (turning the ignition switch ON) and pressing OFF switch for at least 5 seconds. The OFF switch must be pressed within 10 seconds after starting the engine (ignition switch is turned ON). This system will be canceled by either pressing AUTO switch or turning the ignition switch OFF. Shifting from one step is accomplished by means of pressing temperature control switch (driver side), as required.
Shifting from STEP-5 to AUXILIARY MECHANISM is accomplished by means of pressing fan (UP: +) switch.
FUNCTION CONFIRMATION PROCEDURE
1.SET IN SELF-DIAGNOSIS MODE
1. Turn ignition switch ON.
2. Set in self-diagnosis mode as per the following. Press OFF switch for at least 5 seconds Within 10 seconds after starting engine (ignition switch is turned ON).
NOTE:
- If battery voltage drops below 12 V during diagnosis STEP-3, door motor speed becomes slower and as a result, the system may generate an error even when operation is normal. To avoid this, start engine before performing this diagnosis.
- Former STEP-1 (LEDs and display screen are checked) does not exist in this self-diagnosis function.
GO TO 2.
2.STEP-2: SENSOR AND DOOR MOTOR CIRCUITS ARE CHECKED FOR OPEN OR SHORT CIRCUIT
Does code No. 20 appear on the display?
YES - GO TO 3.
NO - GO TO 13.
3.CHECK TO ADVANCE SELF-DIAGNOSIS STEP-3
Press temperature control (UP) switch (driver side).
Advance to self-diagnosis STEP-3?
YES - GO TO 4.
NO - Replace Multifunction switch. (Temperature control switch is malfunctioning.)
4.CHECK TO RETURN SELF-DIAGNOSIS STEP-2
Press temperature control (DOWN) switch (driver side).
Return to self-diagnosis STEP-2?
YES - GO TO 5.
NO - Malfunctioning multifunction switch or unified meter and A/C amp. Refer to Self-Diagnosis.
5.STEP-3: MODE DOOR AND INTAKE DOOR POSITIONS ARE CHECKED
Press temperature control (UP) switch (driver side).
Does code No. 30 appear on the display?
YES - GO TO 6.
NO - GO TO 14.
6.STEP-4: OPERATION OF EACH DOOR MOTOR IS CHECKED
1. Press temperature control (UP) switch (driver side).
2. Press DEF ( ) switch. Code No. of each door motor test is indicated on the display.
GO TO 7.
7.CHECK ACTUATORS
Refer to the following chart and check discharge air flow, air temperature, blower motor duty ratio and compressor operation.
Is this inspection result normal?
YES - GO TO 8.
NO-1 - Air outlet does not change. Refer to Mode Door Motor.
NO-2 - Upper ventilator outlet does not change. Refer to Upper Ventilator Door Motor Circuit.
NO-3 - Intake door does not change. Refer to Intake Door Motor Circuit.
NO-4 - Discharge air temperature does not change. Refer to Air Mix Door Motor Circuit.
NO-5 - Blower motor operation is malfunctioning. Refer to Blower Motor.
NO-6 - Magnet clutch does not engage. Refer to Magnet Clutch.
8.STEP-5: TEMPERATURE OF EACH SENSOR IS CHECKED
1. Press temperature control (UP) switch (driver side).
2. Code No. 51 appears on the display.
GO TO 9.
9.CHECK AMBIENT SENSOR
Press DEF ( ) switch one time. Temperature detected by ambient sensor is indicated on the display.
NOTE:
Check sensor circuit first if the temperature indicated on the display greatly differs from the actual temperature, and then check sensor.
Is this inspection result normal?
YES - GO TO 10.
NO - Go to Ambient Sensor Circuit. Refer to Ambient Sensor.
10.CHECK IN-VEHICLE SENSOR
Press DEF ( ) switch for the second time. Temperature detected by in-vehicle sensor is indicated on the display.
NOTE:
Check sensor circuit first if the temperature indicated on the display greatly differs from the actual temperature, and then check sensor.
Is this inspection result normal?
YES - GO TO 11.
NO - Go to In-vehicle Sensor Circuit.
11.CHECK INTAKE SENSOR
Press DEF ( ) switch for the third time. Temperature detected by intake sensor is indicated on the display.
NOTE:
Check sensor circuit first if the temperature indicated on the display greatly differs from the actual temperature, and then check sensor.
Is this inspection result normal?
YES - GO TO 12.
NO - Go to Intake Sensor Circuit. Refer to Intake Sensor Circuit.
12.CHECK CAN COMMUNICATION ERROR
1. Press intake switch.
2. CAN communication error between each unit that uses the unified meter and A/C amp. can be detected as self-diagnosis results. (If plural errors occur, the display of each error will blink twice for 0 - 5 second intervals.)
Is this inspection result normal?
YES - INSPECTION END
NO - Go to CAN communication (Unified meter and A/C amp.
� AV control unit). Refer to CAN Communication Circuit B2202, "DTC [U1000] CAN
Communication Circuit".
13.CHECK MALFUNCTIONING SENSOR AND DOOR MOTOR
Refer to the following chart for malfunctioning code No.
(Corresponding code Nos. indicates 1 second each if two or more sensors and door motors malfunction.)
(Corresponding code Nos. indicates 0.5 second each if two door motors malfunction.)
When performing indoors, aim a light (more than 60 W) at sunload sensor, otherwise code No. 25 will indicate despite that sunload sensor is functioning properly.
INSPECTION END
14.CHECK MALFUNCTIONING DOOR MOTOR POSITION SWITCH
Door motor PBR is malfunctioning.
INSPECTION END
AUXILIARY MECHANISM: TEMPERATURE SETTING TRIMMER
The trimmer compensates for differences in range of �3�C (�6�F) between temperature setting (displayed digitally) and temperature felt by customer.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to "Self-diagnosis Function".
2. Press fan (UP: +) switch to set system in auxiliary mode.
3. Display shows "61" in auxiliary mechanism. It takes approximately 3 seconds to enable setting operation.
4. Press temperature control switch (driver side) as desired. Temperature will change at a rate of 0.5�C
(1.0�F) each time a switch is pressed.
CAUTION:
A decimal point is not indicated on the display.
NOTE:
When battery cable is disconnected or battery voltage is below 10 V, trimmer operation is canceled. Temperature set becomes that of initial condition, i.e. 0�C (0�F).
AUXILIARY MECHANISM: FOOT POSITION SETTING TRIMMER
Wind distribution ratio in FOOT mode can be set.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to "Self-diagnosis Function".
2. Press fan (UP: +) switch to set system in auxiliary mode.
3. Display shows "61" in auxiliary mechanism. It takes approximately 3 seconds to enable setting operation.
4. Press the mode switch as desired.
NOTE:
When battery cable is disconnected or battery voltage is below 10 V, trimmer operation is canceled. Wind distribution ratio set becomes that of initial condition.
AUXILIARY MECHANISM: INLET PORT MEMORY FUNCTION
When ignition switch is turned from OFF to ON, inlet port memory function at manual mode can be set.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to "Self-diagnosis Function".
2. Press fan (UP: +) switch to set system in auxiliary mode.
3. Display shows "61" in auxiliary mechanism. It takes approximately 3 seconds to enable setting operation
4. Press the intake switch as desired.
NOTE:
When battery cable is disconnected or battery voltage is below 10 V, memory function is canceled. Memory function set becomes that of initial condition.
AUXILIARY MECHANISM: INLET PORT MEMORY FUNCTION
When ignition switch is turned from OFF to ON, inlet port memory function at manual mode can be set.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to "Self-diagnosis Function".
2. Press fan (UP: +) switch to set system in auxiliary mode.
3. Press the intake switch as desired.
NOTE:
When battery cable is disconnected or battery voltage is below 10 V, memory function is canceled. Memory function set becomes that of initial condition.