Mitsubishi Colt Ralliart. Manual — part 663

TROUBLESHOOTING

AUTOMATIC AIR CONDITIONER

55B-13

Step 2. M.U.T.-III data list.
Check that the following service data display con-
tents are normal. (Refer to

P.55B-24

).

• Item 06: Photo sensor

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Go to Step 4.

Step 3. Recheck the trouble symptom

Q: Is the check result normal?

YES :

The trouble can be an intermittent

malfunction (Refer to GROUP 00, How to
Cope with Intermittent Malfunction

P.00-13

).

NO :

Replace the combination meter (meter and
A/C-ECU).

Step 4. Connector check: B-13 photo sensor
connector and B-15 combination meter
connector

AC313823 AM

Connectors: B-13, B-15

Harness side

B-15 (B)

B-15

B-13 (B)

B-13

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Repair the connector.

Step 5. Check the wiring harness between B-13
photo sensor connector (terminal 1 and 2) and
B-15 combination meter connector (terminal 14
and 6).

AC313823 AM

Connectors: B-13, B-15

Harness side

B-15 (B)

B-15

B-13 (B)

B-13

• Check the A/C compressor relay power supply

line for open circuit.

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the wiring harness. Check that the
air conditioner works normally.

Step 6. Replace the photo sensor and recheck
the trouble symptom
Check that the air conditioner works normally.

Q: Is the check result normal?

YES :

This diagnosis is complete.

NO :

Replace the combination meter (meter and
A/C-ECU).

Main

Index

Group

TOC

TROUBLESHOOTING

AUTOMATIC AIR CONDITIONER

55B-14

Inspection Procedure 2: The blower does not work

FUSIBLE
LINK

6

IGNITION
SWITCH (IG2)

BLOWER
RELAY

COMBINATION
METER

METER AND A/C-ECU

BLOWER MOTOR
DRIVE CIRCUIT

BLOWER
MOTOR

POWER
TRANSISTER

Wire colour code
B : Black LG : Light green G : Green L : Blue W : White Y : Yellow SB : Sky blue
BR : Brown O : Orange GR : Gray R : Red P : Pink V : Violet

Blower Motor Circuit

COMMENTS ON TROUBLE SYMPTOM

If the blower motor does not operate, the blower
motor circuit system may be defective.

POSSIBLE CAUSES

• Malfunction of the blower motor.

• Malfunction of the power transistor.

• Malfunction of the combination meter (meter and

A/C-ECU)

• Damaged the wiring harness or connectors

Main

Index

Group

TOC

TROUBLESHOOTING

AUTOMATIC AIR CONDITIONER

55B-15

DIAGNOSIS PROCEDURE

Step 1. M.U.T.-III actuator test
Carry out the actuator test. (Refer to

P.55B-25

)

• Item 01, 02, 03: blower fan

Q: Does the blower motor work normally?

YES :

Go to Step 2.

NO :

Go to Step 3.

Step 2. Recheck the trouble symptom

Q: Is the check result normal?

YES :

Intermittent malfunction (GROUP 00

− How

to Cope with Intermittent Malfunction

P.00-13

).

NO :

Go to Step 19.

Step 3. Connector check: B-116 blower relay
connector

AC313824

Connector: B-116

AD

Junction block side

Junction block (Front view)

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the connector.

Step 4. Check the blower relay.
Refer to GROUP 55A, On-vehicle Service

− Power

relay check

P.55A-52

.

Q: Is the blower relay in good condition?

YES :

Go to Step 5.

NO :

Replace the blower relay.

Step 5. Connector check: B-10 blower motor
connector and B-15 combination meter
connector

AC313823AN

Connectors: B-10, B-15

Harness side

B-15 (B)

B-15

B-10

B-10

Harness side

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the connector.

Main

Index

Group

TOC

TROUBLESHOOTING

AUTOMATIC AIR CONDITIONER

55B-16

Step 6. Voltage measurement at the B-10 blower
motor controller connector.

AC313822

Connector: B-10

AK

Harness side

(1) Disconnect the connector, and measure at the

wiring harness side.

(2) Turn the ignition switch to the ON position.

AC313822 AB

Connector: B-15

Harness side

B-15 (B)

AC309471

AC309471AM

Connector B-15
(Harness side)

(3) Disconnect combination meter connector B-15,

and earth terminal 12.

AC310507

Connector B-10
(Harness side)

FH

(4) measure the voltage between terminal 1 and

body earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 13.

NO :

Go to Step 7.

Step 7. Voltage measurement at B-116 blower
relay connector.

AC313824

Connector: B-116

AD

Junction block side

Junction block (Front view)

(1) Remove the relay, and measure at the junction

block side.

(2) Turn the ignition switch to the ON position.

AC310507 EI

Connector C-116
(Junction block side)

(3) Voltage between terminal 1 and body earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 9.

NO :

Go to Step 8.

Main

Index

Group

TOC