Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnosis Procedure
- CHECK GROUND CONNECTION
- Turn A/C switch and blower fan switch OFF.
- Stop engine.
- Turn ignition switch OFF.
- Check ground connection E38. Refer to "CIRCUIT INSPECTION ".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace ground connection.
- CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
- Disconnect refrigerant pressure sensor harness connector.
- Turn ignition switch ON.
- Check the voltage between refrigerant pressure sensor harness connector and ground.
Refrigerant pressure sensor Ground Voltage Connector Terminal E49 3 Ground Approx. 5 V Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
- DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F1, E8
- Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between refrigerant pressure sensor harness connector and ECM harness connector.
Refrigerant pressure sensor ECM Continuity Connector Terminal Connector Terminal E49 1 F8 48 Existed - Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
- DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E8, F1
- Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Check the continuity between ECM harness connector and refrigerant pressure sensor harness connector.
Refrigerant pressure sensor ECM Continuity Connector Terminal Connector Terminal E49 2 F8 41 Existed - Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 7.
- Check the continuity between ECM harness connector and refrigerant pressure sensor harness connector.
- DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E8, F1
- Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK INTERMITTENT INCIDENT
Refer to "INTERMITTENT INCIDENT ".
Is the inspection result normal?
YES >> Replace refrigerant pressure sensor. Refer to "REFRIGERANT PRESSURE SENSOR: REMOVAL AND INSTALLATION ".
NO >> Repair or replace.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.