Before replacing or repairing air conditioning components, first determine if the malfunction is due to the refrigerant charge, air flow or compressor.
Use the table below to help you find the cause of the problem. The numbers indicate the priority of the likely cause of the problem. Check each part in order. If necessary, replace these parts.
After correcting the malfunction, check the complete system to ensure that performance is satisfactory.
Symptom | Suspect Area |
No blower operation | 1. Blower fuse |
2. Blower relay | |
3. Blower motor | |
4. Blower resistor, Power mosfet or PWM blower module | |
5. Blower speed control switch or knob | |
6. Wire harness | |
No air temperature control | 1. Engine coolant capacity |
2. Heater control assembly | |
3. Temperature control actuator or cable | |
No compressor operation | 1. Refrigerant capacity |
2. A/C Fuse | |
3. Compressor | |
4. A/C pressure transducer | |
5. A/C switch | |
6. Evaporator temperature sensor | |
7. Wire harness | |
8. High CAN | |
No cool comes out | 1. Refrigerant capacity |
2. Refrigerant pressure | |
3. Drive belt | |
4. Compressor | |
5. A/C pressure transducer | |
6. Evaporator temperature sensor | |
7. A/C switch | |
8. Heater control assembly | |
9. Wire harness | |
10. High CAN | |
11. Temperature control actuator or cable | |
Insufficient cooling | 1. Refrigerant capacity |
2. Drive belt | |
3. Compressor | |
4. Condenser | |
5. Expansion valve | |
6. Evaporator | |
7. Refrigerant lines | |
8. A/C pressure transducer | |
9. Heater control assembly | |
10. High CAN | |
No engine idle-up when A/C switch ON | 1. Engine ECM |
2. Wire harness | |
No air inlet control | 1. Heater control assembly |
2. Intake actuator | |
No mode control | 1. Heater control assembly |
2. Mode control actuator or cable | |
No cooling fan operation | 1. Cooling fan fuse |
2. Fan motor | |
3. Blower resistor, Power mosfet or PWM blower module | |
4. Engine ECM | |
5. Wire harness |
