MITSUBISHI ENDEAVOR 2004 Service Repair Manual

The A/C-ECU, the air mixing damper control motor and potentiometer, or
connector(s) or wiring between the two may be defective.
PAST TROUBLE
If DTC B1045 is stored as a past trouble, carry out diagnosis with particular
emphasis on wiring and connector(s) between the A/C-ECU and the air mixing
damper control motor and potentiometer. If the connectors and wiring are
normal, and obviously the ECU is the cause of the trouble, replace the ECU. If
in doubt, do not replace the ECU.
TROUBLESHOOTING HINT
Malfunction of connector. Malfunction of the harness. Malfunction of the air mixing damper control motor and potentiometer. Malfunction of the A/C-ECU.
DIAGNOSIS REQUIRED SPECIAL TOOL:

MB991223: 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, diagnose the CAN bus line.

Use scan tool MB991958 to diagnose the CAN bus lines.
1. Connect scan tool MB991958 to the data link connec
tor.

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

Fig. 66: Connectin
g Scan Tool (MB991958) To Data Link Connector

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

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA
.
2. Turn the ignition switch to "ON" position.
3. Diagnose the CAN bus line.
Q: Is the check result satisfactory?

YES:
Go to Step 2.
NO:
Repair the CAN bus lines (Refer to
CAN BUS DIAGNOSTICS
TABLE
). Then go to Step 7 .
STEP 2. Recheck for diagnostic trouble code.

Recheck if the DTC is set.
1. Erase the DTC.
2. Turn the ignition switch to "ON" position.
3. Check if the DTC is set.
Q: Is the check result satisfactory?

YES:
It can be assumed that this malfunction is intermittent. Refer to
HOW TO USE TROUBLESHOOTING/ INSPECTION SERVICE POINTS
.
NO:
Go to Step 3.
STEP 3. Usin
g scan tool MB991958, check data list item 10, 11, 12: air mix
damper motor.
1. Connect scan tool MB991958 to the data link connec
tor.
CAUTION: To prevent damage to scan tool MB991958,
always turn the ignition switch to the
"LOCK" (OFF) position before connecting or
disconnecting scan tool MB991958.

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

Fig. 67: Connectin
g Scan Tool MB991958 To Data Link Connector

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

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA
.
2. Start the engine.
3. Check the data list.
4. Use scan tool MB991958 to run the actuator test.
Item 10: air mix damper motor (MAX COOL position)
Item 11: air mix damper motor (middle position)
Item 12: air mix damper motor (MAX HOT position)
Check that the air mixing damper control motor operates.
5. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Does the motor operate normally?

YES:
Replace the A/C-ECU. Then go to Step 7 .
NO:
Go to Step 4.
STEP 4. Check A/C-ECU connectors C-16 and air mixing damper control
motor and potentiometer connector C-109 for loose, corroded or damaged
terminals, or terminals pushed back in the connector.

Q: Are A/C-ECU connectors C-16 and air mixing damper control motor
and potentiometer connector C-109 in good condition?

YES:
Go to Step 5.
NO:
Repair or replace the connector. Refer to
HARNESS
CONNECTOR INSPECTION
. Then
go to Ste
p 7 .

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

Fig. 68: Locating Connectors C
-16 And C
-109

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

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

STEP 5. Check the wiring harness between A/C-ECU connector C-16
(terminals 1 and 2) and air mixing damper control motor and
potentiometer connector C-109 (terminals 1 and 2).

Q: Are the wiring harness between A/C-ECU connector C-16 (terminals 1
and 2) and air mixing damper control motor and potentiometer connector
C-109 (terminals 1 and 2) in good condition?

YES:
Go to Step 6.
NO:
Repair the wiring harness. Then go to Step 7 .

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

Fig. 69: Locating Connectors C
-16 And C
-109

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

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

STEP 6. Check the air mixing damper control motor and potentiometer.

Fig. 70: Identifying Damper Position

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Check the air mix dam
per control motor b
y the followin
g procedures.
CAUTION: Do not apply battery voltage when the damper is
in the MAX COOL or MAX HOT position.

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

Fig. 71: Identifying Air Mix Damper Control Motor Checking Procedure

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are the air mixing damper control motor and potentiometer in good
condition?

YES:
Replace the A/C-ECU. Then go to Step 7.
NO:
Replace the air mixing damper control motor and potentiometer. Then go
to Step 7.
STEP 7. Recheck for diagnostic trouble code.

Check a
gain if the DTC is set.

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