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Problem Symptoms Table

FRONT AIR CONDITIONING 

PROBLEM SYMPTOMS

Symptom Suspected area See
All functions do not operate 1. IG power source circuit IG POWER SOURCE CIRCUIT 
2. A/C amplifier TERMINALS OF ECU 
3. Navigation system PROBLEM SYMPTOMS TABLE
Air flow control: no blower operation 1. Heater main relay HEATER RELAY 
2. Blower motor circuit BLOWER MOTOR CIRCUIT 
3. A/C amplifier TERMINALS OF ECU 
4. Blower motor control relay BLOWER MOTOR CONTROL RELAY 
Air flow control: no blower control 1. Blower motor circuit BLOWER MOTOR CIRCUIT 
2. A/C amplifier TERMINALS OF ECU 
3. Solar sensor circuit DTC 21 SOLAR SENSOR CIRCUIT 
4. Blower motor control relay BLOWER MOTOR CONTROL RELAY 
Air flow control: insufficient air flow 1. Blower motor circuit BLOWER MOTOR CIRCUIT 
2. Blower motor control relay BLOWER MOTOR CONTROL RELAY 
Temperature control: no cool air comes out 1. Refrigerant volume REFRIGERANT 
2. Refrigeration system inspection with manifold gauge set REFRIGERANT 
3. Compressor circuit COMPRESSOR CIRCUIT 
4. Pressure switch circuit DTC 23 PRESSURE SWITCH CIRCUIT 
5. Front air mix damper position sensor circuit DTC 31 AIR MIX DAMPER POSITION SENSOR CIRCUIT; DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
6. Front air mix damper control servomotor circuit DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
7. Front room temperature sensor circuit DTC 11 ROOM TEMPERATURE SENSOR CIRCUIT 
8. Ambient temperature sensor circuit DTC 12 AMBIENT TEMPERATURE SENSOR CIRCUIT 
9. A/C amplifier TERMINALS OF ECU 
10. ECM HOW TO PROCEED WITH TROUBLESHOOTING
Temperature control: no warm air comes out 1. Front air mix damper position sensor circuit DTC 31 AIR MIX DAMPER POSITION SENSOR CIRCUIT; DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
2. Front air mix damper control servomotor circuit DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
3. Front room temperature sensor circuit DTC 11 ROOM TEMPERATURE SENSOR CIRCUIT 
4, Ambient temperature sensor circuit DTC 12 AMBIENT TEMPERATURE SENSOR CIRCUIT 
5. Front evaporator temperature sensor circuit DTC 13 EVAPORATOR TEMPERATURE SENSOR CIRCUIT 
6. A/C amplifier TERMINALS OF ECU 
Temperature control: output air is warmer or cooler than the set temperature, or response is slow 1. Refrigerant volume REFRIGERANT 
2. Refrigeration system inspection with manifold gauge set REFRIGERANT 
3. Solar sensor circuit DTC 21 SOLAR SENSOR CIRCUIT 
4. Front room temperature sensor circuit DTC 11 ROOM TEMPERATURE SENSOR CIRCUIT 
5. Ambient temperature sensor circuit DTC 12 AMBIENT TEMPERATURE SENSOR CIRCUIT 
6. Front evaporator temperature sensor circuit DTC 13 EVAPORATOR TEMPERATURE SENSOR CIRCUIT 
7. Front air mix damper position sensor circuit DTC 31 AIR MIX DAMPER POSITION SENSOR CIRCUIT; DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
8. Front air mix damper control servomotor circuit DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
9. Front air inlet damper position sensor circuit DTC 32 AIR INLET DAMPER POSITION SENSOR CIRCUIT; DTC 42 AIR INLET DAMPER CONTROL SERVO MOTOR CIRCUIT 
10. Front air inlet damper control servomotor circuit DTC 42 AIR INLET DAMPER CONTROL SERVO MOTOR CIRCUIT 
11. Condenser CONDENSER 
12. Evaporator DISASSEMBLY 
13. Heater radiator FRONT HEATER UNIT 
14. Expansion valve DISASSEMBLY 
15. A/C amplifier TERMINALS OF ECU 
16. ECM HOW TO PROCEED WITH TROUBLESHOOTING
Temperature control: no temperature control (only max, cool or max, warm) 1. Front room temperature sensor circuit DTC 11 ROOM TEMPERATURE SENSOR CIRCUIT 
2. Ambient temperature sensor circuit DTC 12 AMBIENT TEMPERATURE SENSOR CIRCUIT 
3. Front air mix damper position sensor circuit DTC 31 AIR MIX DAMPER POSITION SENSOR CIRCUIT; DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
4. Front air mix damper control servomotor circuit DTC 41 AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT (PASSENGER SIDE) 
5. A/C amplifier TERMINALS OF ECU 
No air inlet control 1. Front air inlet damper position sensor circuit DTC 32 AIR INLET DAMPER POSITION SENSOR CIRCUIT; DTC 42 AIR INLET DAMPER CONTROL SERVO MOTOR CIRCUIT 
2. Front air inlet damper control servomotor circuit DTC 42 AIR INLET DAMPER CONTROL SERVO MOTOR CIRCUIT 
3. A/C amplifier TERMINALS OF ECU 
No air flow control 1. Air outlet damper position sensor circuit AIR OUTLET CONTROL SERVO MOTOR 
2. Air outlet damper control servomotor circuit AIR OUTLET CONTROL SERVO MOTOR 
3. A/C amplifier TERMINALS OF ECU 
Engine idle up does not occur, or is continuous 1. Compressor circuit COMPRESSOR CIRCUIT 
2. ECM HOW TO PROCEED WITH TROUBLESHOOTING

REAR AIR CONDITIONING 

PROBLEM SYMPTOMS

Symptom Suspected area See
All functions do not operate 1. Rear A/C amplifier TERMINALS OF ECU 
2. IG power source circuit IG POWER SOURCE CIRCUIT 
Air flow control: no blower operation 1. Rear heater main relay HEATER RELAY (FOR REAR HEATER) 
2. Rear blower motor REAR COOLING UNIT 
3. Rear power transistor POWER TRANSISTOR (W/ REAR COOLER) 
4. Rear A/C amplifier TERMINALS OF ECU 
5. IG power source circuit IG POWER SOURCE CIRCUIT 
Air flow control: no blower control 1. Rear heater main relay HEATER RELAY (FOR REAR HEATER) 
2. Rear blower motor REAR COOLING UNIT 
3. Rear power transistor POWER TRANSISTOR (W/ REAR COOLER) 
4. Rear A/C amplifier TERMINALS OF ECU 
5. Solar sensor circuit DTC 21 SOLAR SENSOR CIRCUIT 
Air flow control: insufficient air flow 1. Rear blower motor REAR COOLING UNIT 
2. Rear power transistor POWER TRANSISTOR (W/ REAR COOLER) 
Temperature control: no cool air comes out 1. Refrigerant volume REFRIGERANT 
2. Refrigerant system inspection with manifold gauge set REFRIGERANT 
3. Compressor circuit COMPRESSOR CIRCUIT 
4. Pressure switch circuit DTC 23 PRESSURE SWITCH CIRCUIT 
5. Rear air mix damper position sensor circuit DTC 37 REAR AIR MIX DAMPER POSITION SENSOR CIRCUIT; DTC 47 REAR AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT 
6. Rear air mix damper control servomotor circuit DTC 47 REAR AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT 
7. Rear room temperature sensor circuit DTC 19 REAR ROOM TEMPERATURE SENSOR CIRCUIT 
8. Ambient temperature sensor circuit DTC 12 AMBIENT TEMPERATURE SENSOR CIRCUIT 
9. Rear A/C amplifier TERMINALS OF ECU 
Temperature control: no warmair comes out 1. Rear air mix damper position sensor circuit DTC 37 REAR AIR MIX DAMPER POSITION SENSOR CIRCUIT; DTC 47 REAR AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT 
2. Rear air mix damper control servomotor circuit DTC 47 REAR AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT 
3. Rear room temperature sensor circuit DTC 19 REAR ROOM TEMPERATURE SENSOR CIRCUIT 
4. Ambient temperature sensor circuit DTC 12 AMBIENT TEMPERATURE SENSOR CIRCUIT 
5. Rear evaporator temperature sensor circuit DTC 17 REAR EVAPORATOR TEMPERATURE SENSOR CIRCUIT 
6. Rear A/C amplifier TERMINALS OF ECU 
Temperature control: output air is warmer or cooler than the set temperature or response is slow 1. Refrigerant volume REFRIGERANT 
2. Refrigeration system inspection with manifold gauge set REFRIGERANT 
3. Solar sensor circuit DTC 21 SOLAR SENSOR CIRCUIT 
4. Rear room temperature sensor circuit DTC 19 REAR ROOM TEMPERATURE SENSOR CIRCUIT 
5. Ambient temperature sensor circuit DTC 12 AMBIENT TEMPERATURE SENSOR CIRCUIT 
6. Rear evaporator temperature sensor circuit DTC 17 REAR EVAPORATOR TEMPERATURE SENSOR CIRCUIT 
7. Rear air mix damper position sensor circuit DTC 37 REAR AIR MIX DAMPER POSITION SENSOR CIRCUIT; DTC 47 REAR AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT 
8. Rear air mix damper control servomotor circuit DTC 47 REAR AIR MIX DAMPER CONTROL SERVO MOTOR CIRCUIT 
9. Condenser CONDENSER 
10. Evaporator DISASSEMBLY 
11. Heater radiator DISASSEMBLY 
12. Expansion valve DISASSEMBLY 
13. Rear A/C amplifier TERMINALS OF ECU 
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