Problem Symptoms Table
WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
If a normal system code is displayed during the DTC check but the problem still occurs, check the circuits for each problem symptom in the order given in the table below and proceed to the relevant troubleshooting area below.
HINT:
Inspect the "Fuse" and "Relay" before confirming the suspected area as shown in the charts below.
If any malfunction still exists even after checking and confirming that all the circuits are normal, replace the ECU.
AIR CONDITIONING SYSTEM
| Symptom | Suspected Area | Refer to |
|---|---|---|
| Whole functions of the A/C system does not operate | IG power source circuit | Refer to IG Power Source Circuit |
| Heater control panel power source circuit | Refer to Heater Control Panel Power Source Circuit | |
| LIN communication circuit | Refer to LIN Communication Circuit | |
| Heater control panel | Refer to REMOVAL | |
| A/C amplifier | Refer to REMOVAL | |
| Air Flow Control: No blower operation | IG power source circuit | Refer to IG Power Source Circuit |
| Blower motor circuit | Refer to Blower Motor Circuit | |
| Heater control panel power source circuit | Refer to Heater Control Panel Power Source Circuit | |
| LIN communication circuit | Refer to LIN Communication Circuit | |
| Heater control panel | Refer to REMOVAL | |
| A/C amplifier | Refer to REMOVAL | |
| Air Flow Control: No blower control | Blower motor circuit | Refer to Blower Motor Circuit |
| Room temperature sensor circuit | Refer to DTC B1411/11: Room Temperature Sensor Circuit | |
| Ambient temperature sensor circuit | Refer to DTC B1412/12: Ambient Temperature Sensor Circuit | |
| Solar sensor circuit (Driver side) | Refer to DTC B1424/24: Solar Sensor Circuit (Driver Side) | |
| Solar sensor circuit (Passenger side) | Refer to DTC B1421/21: Solar Sensor Circuit (Passenger Side) | |
| A/C amplifier | Refer to REMOVAL | |
| Air Flow Control: Insufficient air flow | Blower motor circuit | Refer to Blower Motor Circuit |
| Temperature Control: No cool air comes out | Blower motor circuit | Refer to Blower Motor Circuit |
| Air mix control servo motor circuit (Driver side) | Refer to DTC B1446/46: Air Mix Damper Control Servo Motor Circuit (Driver Side) | |
| Air mix control servo motor circuit (Passenger side) | Refer to DTC B1441/41: Air Mix Damper Control Servo Motor Circuit (Passenger Side) | |
| Room temperature sensor circuit | Refer to DTC B1411/11: Room Temperature Sensor Circuit | |
| Ambient temperature sensor circuit | Refer to DTC B1412/12: Ambient Temperature Sensor Circuit | |
| Evaporator temperature sensor circuit | Refer to DTC B1413/13: Evaporator Temperature Sensor Circuit | |
| Pressure switch circuit | Refer to DTC B1423/23: Pressure Sensor Circuit | |
| Compressor circuit | Refer to Compressor Circuit | |
| Compressor lock sensor circuit | Refer to DTC B1422/22: Compressor Lock Sensor Circuit | |
| Compressor solenoid circuit | Refer to DTC B1451/51: Compressor Solenoid Circuit | |
| A/C amplifier | Refer to REMOVAL | |
| Temperature Control: No Warm air comes out | Steering pad switch circuit | Refer to Steering Pad Switch Circuit |
| Air mix control servo motor circuit (Driver side) | Refer to DTC B1446/46: Air Mix Damper Control Servo Motor Circuit (Driver Side) | |
| Air mix control servo motor circuit (Passenger side) | Refer to DTC B1441/41: Air Mix Damper Control Servo Motor Circuit (Passenger Side) | |
| Room temperature sensor circuit | Refer to DTC B1411/11: Room Temperature Sensor Circuit | |
| Ambient temperature sensor circuit | Refer to DTC B1412/12: Ambient Temperature Sensor Circuit | |
| Evaporator temperature sensor circuit | Refer to DTC B1413/13: Evaporator Temperature Sensor Circuit | |
| Solar sensor circuit (Driver side) | Refer to DTC B1424/24: Solar Sensor Circuit (Driver Side) | |
| Solar sensor circuit (Passenger side) | Refer to DTC B1421/21: Solar Sensor Circuit (Passenger Side) | |
| A/C amplifier | Refer to REMOVAL | |
| Temperature Control: Output is warmer or cooler than the set temperature or response is slow | Steering pad switch circuit | Refer to Steering Pad Switch Circuit |
| Air mix control servo motor circuit (Driver side) | Refer to DTC B1446/46: Air Mix Damper Control Servo Motor Circuit (Driver Side) | |
| Air mix control servo motor circuit (Passenger side) | Refer to DTC B1441/41: Air Mix Damper Control Servo Motor Circuit (Passenger Side) | |
| Room temperature sensor circuit | Refer to DTC B1411/11: Room Temperature Sensor Circuit | |
| Ambient temperature sensor circuit | Refer to DTC B1412/12: Ambient Temperature Sensor Circuit | |
| Evaporator temperature sensor circuit | Refer to DTC B1413/13: Evaporator Temperature Sensor Circuit | |
| Solar sensor circuit (Driver side) | Refer to DTC B1424/24: Solar Sensor Circuit (Driver Side) | |
| Solar sensor circuit (Passenger side) | Refer to DTC B1421/21: Solar Sensor Circuit (Passenger Side) | |
| A/C amplifier | Refer to REMOVAL | |
| Temperature Control: No temperature control (only Max. cool or Max. warm) | Steering pad switch circuit | Refer to Steering Pad Switch Circuit |
| Air mix control servo motor circuit (Driver side) | Refer to DTC B1446/46: Air Mix Damper Control Servo Motor Circuit (Driver Side) | |
| Air mix control servo motor circuit (Passenger side) | Refer to DTC B1441/41: Air Mix Damper Control Servo Motor Circuit (Passenger Side) | |
| Room temperature sensor circuit | Refer to DTC B1411/11: Room Temperature Sensor Circuit | |
| Ambient temperature sensor circuit | Refer to DTC B1412/12: Ambient Temperature Sensor Circuit | |
| Evaporator temperature sensor circuit | Refer to DTC B1413/13: Evaporator Temperature Sensor Circuit | |
| Solar sensor circuit (Driver side) | Refer to DTC B1424/24: Solar Sensor Circuit (Driver Side) | |
| Solar sensor circuit (Passenger side) | Refer to DTC B1421/21: Solar Sensor Circuit (Passenger Side) | |
| A/C amplifier | Refer to REMOVAL | |
| No air inlet control | Air inlet control servo motor circuit | Refer to DTC B1442/42: Air Inlet Damper Control Servo Motor Circuit |
| A/C amplifier | Refer to REMOVAL | |
| No air flow mode control | Air outlet control servo motor circuit | Refer to DTC B1443/43: Air Outlet Damper Control Servo Motor Circuit |
| A/C amplifier | Refer to REMOVAL | |
| Blinking of A/C indicator | Compressor solenoid circuit | Refer to DTC B1451/51: Compressor Solenoid Circuit |
| Diagnostic trouble code are not recorded. Set mode is cleared when ignition switch is turned off. | Back up power source circuit | Refer to Back-up Power Source Circuit |
| Engine idle up does not occur, or is continuous | Compressor circuit | Refer to Compressor Circuit |
| Compressor lock sensor circuit | Refer to DTC B1422/22: Compressor Lock Sensor Circuit | |
| Compressor solenoid circuit | Refer to DTC B1451/51: Compressor Solenoid Circuit | |
| A/C amplifier | Refer to REMOVAL | |
| Set temperature value displayed does not much up with operation of temperature control switch. | Heater control panel power source circuit | Refer to Heater Control Panel Power Source Circuit |
| LIN communication circuit | Refer to LIN Communication Circuit | |
| Heater control panel | Refer to REMOVAL | |
| A/C amplifier | Refer to REMOVAL | |
| The seat heater switch indicator does not come on. | Seat heater control power source circuit | Refer to Seat Heater Control Power Source Circuit |
| Seat heater indicator circuit | Refer to Seat Heater Switch Indicator Circuit | |
| Seat heater control sub-assembly | Refer to DISASSEMBLY - Step 37 | |
| A/C amplifier | Refer to REMOVAL | |
| Unable to access diagnosis mode. | A/C amplifier | Refer to REMOVAL |
| Unable to control A/C with the steering pad switch | Steering pad switch circuit | Refer to Steering Pad Switch Circuit |
| Heater control panel power source circuit | Refer to Heater Control Panel Power Source Circuit | |
| LIN communication circuit | Refer to LIN Communication Circuit | |
| Heater control panel | Refer to REMOVAL | |
| A/C amplifier | Refer to REMOVAL | |
| DTC not recorded. Set mode is cleared when the ignition switch is turned off. | Back up power source circuit | Refer to Back-up Power Source Circuit |
| A/C amplifier | Refer to REMOVAL | |
| Seat heater does not operate. | Seat heater switch circuit | Refer to Seat Heater Switch Circuit |
| Seat heater control power source circuit | Refer to Seat Heater Control Power Source Circuit | |
| Seat heater temperature sensor circuit (Driver side) | Refer to DTC B1463/63: Driver Side Seat Heater Temperature Sensor Circuit | |
| Seat heater temperature sensor circuit (Passenger side) | Refer to DTC B1464/64: Front Passenger Side Seat Heater Temperature Sensor Circuit | |
| Seat heater control sub-assembly | Refer to DISASSEMBLY - Step 37 | |
| A/C amplifier | Refer to REMOVAL | |
| Seat ventilators do not operate. | Seat heater switch circuit | Refer to Seat Heater Switch Circuit |
| Seat heater control power source circuit | Refer to Seat Heater Control Power Source Circuit | |
| Seat blower control circuit | Refer to Seat Blower Control Circuit | |
| Seat heater control sub-assembly | Refer to DISASSEMBLY - Step 37 | |
| Seat climate control blower | Refer to DISASSEMBLY |