1999 MITSUBISHI LANCER EVOLUTION VI ECU

FULL-AUTOMATIC AIR CONDITIONER – Troubleshooting55-48
Inspection procedure 11
Inside/outside air changeover is not possible.
Probable cause
If inside/outside air changeover is not possible even when the inside/outside air
changeover switch is on, the cause is probably a malfunction of the
inside/outside air changeover damper motor.
Malfunction of inside/outside air changeover
damper motor

Malfunction of inside/outside air changeover
damper

Malfunction of connector or harness

Malfunction of A/C-ECU
Can an operating sound be heard when the inside/outside air
changeover switch is operated?NOInspection procedure 15 (Refer to P.55-52.)
YES
Inside/outside air changeover damper motor check (Refer to
P.55-59.)NG
Replace
OK
Measure at the inside/outside air changeover damper motor con-
nector B-36.

Disconnect the connector, and measure at the harness
side connector.

Outside air select button: ON

Voltage between terminal (3) and body earth
OK:10 V

Inside air select button: ON

Voltage between terminal (1) and body earth
OK:10 VNGCheck the following connector:
B-05
NG
Repair OK
Check the trouble symptom.
NG
Check the harness between the inside/outside air changeover
damper motor and the A/C-ECU, and repair if necessary.
NG
Repair OK
Replace the A/C-ECU.
OK
Check the following connector:
B-36NG
Repair
OK
Check the trouble symptom.
NG
Inside/outside air changeover damper checkNG
Repair
OK
Replace the A/C-ECU.

FULL-AUTOMATIC AIR CONDITIONER – Troubleshooting55-49
Inspection procedure 12
Defroster function does not operate.
Probable cause
If the defroster function does not operate when the defroster switch is turned
on, the cause is probably a malfunction of the A/C or of the air outlet port
changeover circuit.
Malfunction of air conditioner drive system

Malfunction of air outlet changeover damper drive
system

Malfunction of connector or harness

Malfunction of A/C-ECU
Can an operating sound be heard when the defroster switch is
operated?NOInspection procedure 15 (Refer to P.55-52.)
YES
Does the A/C operate?NOInspection procedure 2 (Refer to P.55-43.)
YES
Can the air outlet port be changed over?NOInspection procedure 10 (Refer to P.55-47.)
YES
Air outlet changeover damper (for defroster) checkNG
Repair
OK
Replace the A/C-ECU.

FULL-AUTOMATIC AIR CONDITIONER – Troubleshooting55-50
Inspection procedure 13
Condenser fan does not operate.
Probable cause
If the condenser fan does not turn when the A/C is ON, the cause is probably
a malfunction of the condenser fan motor activation circuit. In this case, reduced
cooling performance will be caused if the vehicle is not running.
Malfunction of condenser fan motor

Malfunction of condenser fan motor relay (HI, LO)

Malfunction of wiring harness or connector
NG
Repair OK
Check the trouble symptom.
NG
Check the harness between the condenser fan motor relay (LO)
and the condenser fan motor, and repair if necessary.
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the condenser fan motor relay (LO)
and the body earth, and repair if necessary.
OK
Measure at the condenser fan motor relay (LO) connector A-113X.

Disconnect the connector.
(1) Continuity between terminal (4) and body earth
OK:Continuity
(2) Voltage between terminal (2) and body earth
OK:System voltage
(3) Voltage between terminal (1) and body earth
OK:System voltage(1) NGCheck the following connector:
A-113X
Condenser fan motor check (Refer to P.55-29.)NG
Replace
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the condenser fan motor relay (LO)
and the A/C-ECU, and repair if necessary.
(2) NG
Check the following connector:
A-113X
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the condenser fan motor relay (LO)
and the fusible link 2, and repair if necessary.
(3) NG
Check the following connector:
A-113X
OK
Continued to the next page
OK
Measure at the condenser fan motor connector A-99.

Disconnect the connector, and measure at the harness
side connector.

Connect the connector A-113X terminal (2) to the battery.

Voltage between terminal (2) and body earth
OK:System voltageNGCheck the following connector:
A-113X
OK
Condenser fan motor relay check (Refer to P.55-14.)NG
Replace

FULL-AUTOMATIC AIR CONDITIONER – Troubleshooting55-51
NG
Repair OK
Check the trouble symptom.
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the condenser fan motor relay (HI)
and the engine-ECU, and repair if necessary.
Measure at the radiator fan motor relay (HI) connector A-114X.

Disconnect the connector.
(1) Continuity between 4-B-59 and connector terminal (20)
OK:Continuity
(2) Voltage between terminal (2) and body earth (Ignition
switch: ON)
OK:System voltage
(3) Voltage between terminal (1) and body earth
OK:System voltage(1) NGCheck the following connectors:
A-114X, A-28, B-59
From the previous page
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the condenser fan motor relay (HI)
and the ignition switch, and repair if necessary.
(2) NG
Check the following connector:
A-114X
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the condenser fan motor relay (HI)
and the fusible link 2, and repair if necessary.
(3) NG
Check the following connector:
A-114X
OK
Measure at the condenser fan motor connector A-99.

Disconnect the connector, and measure at the harness
side connector.

Connect the terminal B-59 to the earth.

Voltage between terminal (1) and body earth (Ignition switch:
ON)
OK:System voltageNOCheck the following connector:
A-112X
NG
Check the harness between the condenser fan motor relay (HI)
and the condenser fan motor, and repair if necessary.
Inspection procedure 14
Rear defogger does not operate.
Probable cause
If the rear defogger does not operate when the rear defogger switch is turned
on (timer operates for 20 minutes), the cause is probably a malfunction of the
A/C-ECU power supply system (earth).
Malfunction of connector or harness

Malfunction of A/C-ECU
Can an operating sound be heard when the rear defogger switch
is operated?NOInspection procedure 15 (Refer to P.55-52.)
YES
Replace the A/C-ECU.

FULL-AUTOMATIC AIR CONDITIONER – Troubleshooting55-52
Inspection procedure 15
A/C-ECU power supply circuit check
NG
Repair OK
Check the trouble symptom.
NG
Check the harness between the A/C-ECU and the fusible link
No.1, and repair if necessary.
OK
Check the trouble symptom.
NG
Check the harness between the A/C-ECU and the junction block,
and repair if necessary.
OK
Check the following connector:
B-05NG
Repair
OK
Check the trouble symptom.NGReplace the A/C-ECU.
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the A/C-ECU and the body earth,
and repair if necessary.
NG
Repair
OK
Measure at the A/C-ECU connector B-05.

Disconnect the connector, and measure at the harness
side connector.

Continuity between terminal (29) and body earth
OK:Continuity

Continuity between terminal (35) and body earth
OK:ContinuityNGCheck the following connectors:
B-05, B-48, B-19, B-69, B-80
OK
Measure at the A/C-ECU connector B-05.

Disconnect the connector, and measure at the harness
side connector.

Voltage between terminal (28) and body earth (Ignition
switch: ON)
OK:System voltageNGCheck the following connectors:
B-49, B-75, B-76
Measure at the A/C-ECU connector B-04.

Disconnect the connector, and measure at the harness
side connector.

Voltage between terminal (3) and body earth
OK:System voltageNGCheck the following connectors:
B-49, B-75, B-73

FULL-AUTOMATIC AIR CONDITIONER – Troubleshooting55-53
Inspection procedure 16
A/C compressor control circuit check
Measure at the A/C-ECU connector B-05.

Blower switch and A/C switch: ON

Setting temperature: 17C

Connect the connector.

Voltage between terminal (34) and body earth (Ignition
switch: ON)
OK:System voltageNGCheck the following connector:
B-05
NG
Repair OK
Check the trouble symptom.
NG
Replace the A/C-ECU.
OK
Measure at the A/C compressor relay connector A-116X.

Disconnect the connector, and measure at the harness
side connector.

Voltage between terminal (2) and body earth
OK:System voltageNGCheck the following connectors:
A-49, B-15, B-05
NG
Repair OK
Check the trouble symptom.
NG
Check the harness between the A/C-ECU and the A/C compressor
relay, and repair if necessary.
OK
Measure at the engine-ECU connector B-54 or B-59.

Disconnect the connector, and measure at the harness
side connector.

Voltage between terminal (21) or (22) and body earth
OK:System voltageNGCheck the following connectors:
A-28, A-116X
NG
Repair OK
Check the trouble symptom.
NG
Check the harness between the A/C compressor relay and the
engine-ECU, and repair if necessary.
OK
Replace the engine-ECU.

FULL-AUTOMATIC AIR CONDITIONER – Troubleshooting55-54
DATA LIST REFERENCE TABLE
Check itemCheck conditionNormal condition
Inside air temperature sensor

MUT-II (11)Ignition switch: ONInside air temperature and temper-
ature displayed on the MUT-II are
identical.
Outside air temperature sen-
sor

MUT-II (13)Ignition switch: ONOutside air temperature and tem-
perature displayed on the MUT-II
are identical.
Heater water temperature
sensor

MUT-II (15)Ignition switch: ONHeater core surface temperature
and temperature displayed on the
MUT-II are identical.
Air thermo sensor

MUT-II (21)Ignition switch: ONEvaporator surface temperature
and temperature displayed on the
MUT-II are identical.
Photo sensor

MUT-II (25)Ignition switch: ONAmount of incident light is propor-
tional to voltage displayed on the
MUT-II.
Air mix damper potentiometer

MUTII(31)
Ignition switch: ONDamper positionOpening degree (%)

MUT-II (31)MAX. HOTApprox. 100
MAX. COOLApprox. 0
Air outlet changeover damper
potentiometer
Ignition switch: ONDamper positionOpening degree (%)
potentiometer

MUT-II (32)FACEApprox. 0
FOOTApprox. 50
FOOT/DEF.Approx. 75
DEF.Approx. 100
CHECK AT THE A/C-ECU TERMINALS
A/C-ECU
The parenthesized values in “Normal condition” column are for your reference.
Terminal
No.
Check itemCheck conditionNormal condition
1Front power transistor collector outputWhen blower switch is at OFFSystem voltage
When blower switch is at LOApprox. 7 V
When blower switch is at HIAlmost no voltage (0 V)
2Front power transistor base outputWhen blower switch is at OFF0 V
When blower switch is at LOApprox. 1.3 V
When blower switch is at HIApprox. 2.5 V
3BackupAt all timesSystem voltage

C-1
ELECTRICAL
WIRING
(R.H. DRIVE VEHICLES)
CONTENTS
GENERAL 3. . . . . . . . . . . . . . . . . . . . . . . . . .
WIRING HARNESS CONFIGURATION
DIAGRAMS 4. . . . . . . . . . . . . . . . . . . . . . . . .
ENGINE COMPARTMENT 4. . . . . . . . . . . . . . . .
DASH PANEL 8. . . . . . . . . . . . . . . . . . . . . . . . . . .
FLOOR AND ROOF 12. . . . . . . . . . . . . . . . . . .
LUGGAGE COMPARTMENT 14. . . . . . . . . . . .
SINGLE PART INSTALLATION
POSITION 16. . . . . . . . . . . . . . . . . . . . . . . . .
RELAY 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ECU 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SENSOR 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SOLENOID AND SOLENOID VALVE 19. . . .
INSPECTION CONNECTOR 20. . . . . . . . . . . .
FUSIBLE LINK AND FUSE 20. . . . . . . . . . . . .
EARTH CABLE 21. . . . . . . . . . . . . . . . . . . . . . . .
EARTH 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CIRCUIT DIAGRAM 23. . . . . . . . . . . . . . . .
CENTRALIZED JUNCTION 23. . . . . . . . . . . . .
POWER DISTRIBUTION SYSTEM 24. . . . . .
STARTING SYSTEM 29. . . . . . . . . . . . . . . . . . .
IGNITION SYSTEM 30. . . . . . . . . . . . . . . . . . . .
CHARGING SYSTEM 31. . . . . . . . . . . . . . . . . .
MPI SYSTEM 32. . . . . . . . . . . . . . . . . . . . . . . . . .
COOLING SYSTEM 38. . . . . . . . . . . . . . . . . . . .
HEADLAMP 40. . . . . . . . . . . . . . . . . . . . . . . . . . .
TAIL LAMP, POSITION LAMP, LICENCE
PLATE LAMP AND LIGHTING MONITOR
BUZZER 42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ROOM LAMP AND LUGGAGE
COMPARTMENT LAMP 45. . . . . . . . . . . . . . . .
IGNITION KEY CYLINDER ILLUMINATION
LAMP 46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TURN-SIGNAL LAMP AND
HAZARD WARNING LAMP 48. . . . . . . . . . . . .
CONTINUED ON NEXT PAGE