2004 MITSUBISHI ENDEAVOR Ac pressure sensor

relay system may be defective. TROUBLESHOOTING HINTS
Improper amount of refrigerant Malfunction of the air thermo sensor Malfunction of the ambient air temperature sensor Malfunction of the A/C pressure sensor Malfunction of the A/C compressor clutch relay Malfunction of the A/C refrigerant temperature switch Malfunction of the air conditioning compressor clutch Malfunction of the A/C-ECU Malfunction of the PCM Damaged harness wires or connectors
DIAGNOSIS REQUIRED SPECIAL TOOLS:

MB991223: Test Harness Set MB991958: Scan Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.) MB991827: MUT-III USB Cable MB991910: MUT-III Main Harness A (Vehicles with CAN
communication system)
STEP 1. Check the defogger and outside/inside air selection damper
control motor operation.

Q: Do the defogger and outside/inside air selection damper control motor
work normally?

YES:
Go to Step 2.
NO:
Refer to
INSPECTION PROCEDURE 10 MALFUNCTION OF
THE A/C
-ECU POWER SUPPLY SYSTEM
.

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor

Fig. 169: Connector Terminal Resistance (2 Of 2)

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

STEP 22. Check the A/C pressure sensor operation.

1. Assemble a gauge manifold on the high pressure service valve.
2. Disconnect the A/C pressure sensor connector and connect special tool test
harness MB991658 as shown in the illustration.

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor

Fig. 170: Identifying A/C Pressure Sensor Connector

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

3. Turn ON the engine and then turn ON the air conditioner switch.
4. At this time, check to see that the voltage of A/C pressure sensor terminal
No.2 reflects the specifications of the figure.

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor

Fig. 171: Checking Voltage Of A/C Pressure Sensor

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Is the A/C pressure sensor operating properly?

YES:
Go to Step 23.
NO:
Replace the A/C pressure sensor. Check that the air conditioning
works normally.
NOTE: The allowance shall be defined as +/-5%

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor

STEP 8. Replace the power transistor.

Q: Does the blower motor operate normally?

YES:
It can be assumed that this malfunction is intermittent. Refer to
HOW TO USE TROUBLESHOOTING/ INSPECTION SERVICE POINTS
.
NO:
Replace the A/C-ECU. Check that the air conditioning works
normally.
INSPECTION PROCEDURE 7: THE A/C INDICATOR FLASHES TECHNICAL DESCRIPTION (COMMENT) If the A/C indicator flashes, inadequate refrigerant quantity, the ambient air
temperature sensor circuit or the A/C pressure sensor circuit is suspected. TROUBLESHOOTING HINTS
Malfunction of the A/C pressure sensor Malfunction of the ambient air temperature sensor Malfunction of the A/C-ECU
DIAGNOSIS Required Special Tools:

MB991223: Test Harness Set MB991958: Scan Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.) MB991827: MUT-III USB Cable MB991910: MUT-III Main Harness A (Vehicles with CAN
communication system)
STEP 1. Using scan tool MB991958, read the diagnostic trouble code.

Check if an A/
C-ECU DTC is set.

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor

Required Special Tools:

MB991658: Test Harness
1. Assemble a gauge manifold on the high pressure service valve.
2. Disconnect the A/C pressure sensor connector and connect special tool
MB991658 as shown in the illustration.
3. Turn ON the engine and then turn ON the air conditioner switch. Fig. 271: Identifying A/C Pressure Sensor Connector

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor

Fig. 272: Connecting Special Tool (MB991658)

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

4. At this time, check to see that the voltage of A/C pressure sensor terminal No.2
reflects the specifications of the figure.
NOTE: The allowance shall be defined as +/-5%.

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor

Fig. 273: Voltage Of A/C Pressure Sensor

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

COMPRESSOR DRIVE BELT ADJUSTMENT Refer to
7. DRIVE BELTS (FOR GENERATOR, POWER STEERING OIL
PUMP AND AIR CONDITIONING
.
CHARGING Use the refrigerant recovery station to charge the refrigerant. METHOD BY USING REFRIGERANT RECOVERY AND RECYCLING UNIT Using the refrigerant recovery and recycling unit, refill the refrigerant. NOTE: Refer to the REFRIGERANT RECOVERY AND RECYCLING
UNIT'S INSTRUCTION MANUAL FOR OPERATION OF THE

2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor