Problem Symptoms Table
WARNING: This page is about a different car, the 2008 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
AIR CONDITIONING SYSTEM:
AIR CONDITIONER SYMPTOMS REFERENCE
| Symptom | Suspected area | See |
|---|---|---|
| Entire A/C system does not operate | 1. IG power source circuit | IG POWER SOURCE CIRCUIT |
| 2. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| Air Flow Control: No blower operation | 1. Blower motor circuit | BLOWER MOTOR CIRCUIT |
| 2. Heater relay circuit | HEATER RELAY CIRCUIT | |
| 3. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| Air Flow Control: No blower control | 1. Blower motor circuit | BLOWER MOTOR CIRCUIT |
| 2. Heater relay circuit | HEATER RELAY CIRCUIT | |
| 3. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| Air Flow Control: Insufficient air output | 1. Blower motor circuit | BLOWER MOTOR CIRCUIT |
| 2. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| Temperature Control: No cool air comes out | 1. Volume of refrigerant | REFRIGERANT |
| 2. Drive belt tension | - | |
| 3. Refrigerant pressure | REFRIGERANT | |
| 4. Air conditioning compressor magnetic clutch circuit | AIR CONDITIONING COMPRESSOR MAGNETIC CLUTCH CIRCUIT | |
| 5. Compressor solenoid circuit | DTC B1451/51 COMPRESSOR SOLENOID CIRCUIT | |
| 6. Compressor lock sensor circuit | DTC B1422/22 COMPRESSOR LOCK SENSOR CIRCUIT | |
| 7. Pressure sensor circuit | DTC B1423/23 PRESSURE SENSOR CIRCUIT | |
| 8. Air mix damper control servomotor circuit (Driver side) | DTC B1446/46 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (DRIVER SIDE) | |
| 9. Air mix damper control servomotor circuit (Passenger side) | DTC B1441/41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) | |
| 10. Air mix damper position sensor circuit (Driver side) | DTC B1436/36 AIR MIX DAMPER POSITION SENSOR CIRCUIT (DRIVER SIDE) | |
| 11. Air mix damper position sensor circuit (Passenger side) | DTC B1431/31 AIR MIX DAMPER POSITION SENSOR CIRCUIT (PASSENGER SIDE) | |
| 12. Room temperature sensor circuit | DTC B1411/11 ROOM TEMPERATURE SENSOR CIRCUIT | |
| 13. Ambient temperature sensor circuit | DTC B1412/12 AMBIENT TEMPERATURE SENSOR CIRCUIT | |
| 14. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| 15. Multiplex communication circuit | DTC B1499/99 MULTIPLEX COMMUNICATION CIRCUIT | |
| Temperature Control: No warm air comes out | 1. Air mix damper control servomotor circuit (Driver side) | DTC B1446/46 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (DRIVER SIDE) |
| 2. Air mix damper control servomotor circuit (Passenger side) | DTC B1441/41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) | |
| 3. Air mix damper position sensor circuit (Driver side) | DTC B1436/36 AIR MIX DAMPER POSITION SENSOR CIRCUIT (DRIVER SIDE) | |
| 4. Air mix damper position sensor circuit (Passenger side) | DTC B1431/31 AIR MIX DAMPER POSITION SENSOR CIRCUIT (PASSENGER SIDE) | |
| 5. Ambient temperature sensor circuit | DTC B1412/12 AMBIENT TEMPERATURE SENSOR CIRCUIT | |
| 6. Room temperature sensor circuit | DTC B1411/11 ROOM TEMPERATURE SENSOR CIRCUIT | |
| 7. Evaporator temperature sensor circuit | DTC B1413/13 EVAPORATOR TEMPERATURE SENSOR CIRCUIT | |
| 8. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| 9. Multiplex communication circuit | DTC B1499/99 MULTIPLEX COMMUNICATION CIRCUIT | |
| 10. Heater radiator | AIR CONDITIONING UNIT | |
| Temperature Control: Output air is warmer or cooler than set temperature or response is slow | 1. Room temperature sensor circuit | DTC B1411/11 ROOM TEMPERATURE SENSOR CIRCUIT |
| 2. Ambient temperature sensor circuit | DTC B1412/12 AMBIENT TEMPERATURE SENSOR CIRCUIT | |
| 3. Solar sensor circuit (Driver side) | DTC B1424/24 SOLAR SENSOR CIRCUIT (DRIVER SIDE) | |
| 4. Solar sensor circuit (Passenger side) | DTC B1421/21 SOLAR SENSOR CIRCUIT (PASSENGER SIDE) | |
| 5. Air mix damper control servomotor circuit (Driver side) | DTC B1446/46 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (DRIVER SIDE) | |
| 6. Air mix damper control servomotor circuit (Passenger side) | DTC B1441/41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) | |
| 7. Air mix damper position sensor circuit (Driver side) | DTC B1436/36 AIR MIX DAMPER POSITION SENSOR CIRCUIT (DRIVER SIDE) | |
| 8. Air mix damper position sensor circuit (Passenger side) | DTC B1431/31 AIR MIX DAMPER POSITION SENSOR CIRCUIT (PASSENGER SIDE) | |
| 9. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| 10. Multiplex communication circuit | DTC B1499/99 MULTIPLEX COMMUNICATION CIRCUIT | |
| Temperature Control: No temperature control (only Max. cool or Max. warm) | 1. Air mix damper control servomotor circuit (Driver side) | DTC B1446/46 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (DRIVER SIDE) |
| 2. Air mix damper control servomotor circuit (Passenger side) | DTC B1441/41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) | |
| 3. Air mix damper position sensor circuit (Driver side) | DTC B1436/36 AIR MIX DAMPER POSITION SENSOR CIRCUIT (DRIVER SIDE) | |
| 4. Air mix damper position sensor circuit (Passenger side) | DTC B1431/31 AIR MIX DAMPER POSITION SENSOR CIRCUIT (PASSENGER SIDE) | |
| 5. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| No air inlet control | 1. Air inlet damper control servomotor circuit | DTC B1442/42 AIR INLET DAMPER CONTROL SERVO MOTOR CIRCUIT |
| 2. Air inlet damper position sensor circuit | DTC B1432/32 AIR INLET DAMPER POSITION SENSOR CIRCUIT | |
| 3. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| No air outlet control | 1. Air outlet damper control servomotor circuit | DTC B1443/43 AIR OUTLET DAMPER CONTROL SERVO MOTOR CIRCUIT |
| 2. Air outlet damper position sensor circuit | DTC B1433/33 AIR OUTLET DAMPER POSITION SENSOR CIRCUIT | |
| 3. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| Engine idle up does not occur, or is continuous | 1. Air conditioning compressor magnetic clutch circuit | AIR CONDITIONING COMPRESSOR MAGNETIC CLUTCH CIRCUIT |
| 2. Compressor solenoid circuit | DTC B1451/51 COMPRESSOR SOLENOID CIRCUIT | |
| 3. Compressor lock sensor circuit | DTC B1422/22 COMPRESSOR LOCK SENSOR CIRCUIT | |
| 4. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| 5. Multiplex communication circuit | DTC B1499/99 MULTIPLEX COMMUNICATION CIRCUIT | |
| Displayed set temperature value does not match up with operation of temperature control switch | A/C amplifier | AIR CONDITIONING AMPLIFIER |
| Brightness does not change when rheostat volume or light control switch is adjusted | 1. Illumination light system | SYSTEM DESCRIPTION |
| 2. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| Unable to access diagnostic mode | A/C amplifier | AIR CONDITIONING AMPLIFIER |
| DTCs are not recorded. Set mode is cleared when IG switch is turned off | 1. Back-up power source circuit | BACK-UP POWER SOURCE CIRCUIT |
| 2. A/C amplifier | AIR CONDITIONING AMPLIFIER | |
| Blinking of A/C indicator | 1. Compressor solenoid circuit | DTC B1451/51 COMPRESSOR SOLENOID CIRCUIT |
| 2. A/C amplifier | AIR CONDITIONING AMPLIFIER |