ECU MITSUBISHI LANCER EVOLUTION 2007 Service Repair Manual

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-3
TROUBLESHOOTING
BASIC FLOW OF TROUBLESHOOTING
Refer to Group 00 – How to Use Troubleshooting/Inspection Service Points.
INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptomInspection procedureReference page
Air conditioner not working at all155 - 3
Blower motor not working255 - 4
Air cannot be switched between inside and outside355 - 5
Rear defogger not working455-6
Cold air not coming out from the air outlet555 - 7
Magnet clutch not working normally655 - 8
Condenser fan not working at all755-9
Condenser fan not working only for LO855-10
Condenser fan not working only for HI955-11
INSPECTION PROCEDURE FOR TROUBLE SYMPTOM
Inspection procedure 1
Air conditioner not working at all
Probable cause
The A/C-ECU power supply system (including earth) may be defective.DHarness or connector fault
DA/C-ECU fault
NG
Repair
NG
Check the harness between the Ignition switch (IG2) and the
A/C-ECU, and repair if necessary.
NG
Repair
NG
Check the harness between the A/C-ECU and body earth, and
repair if necessary.
NG
Replace manual air conditioner control panel (A/C-ECU).
OK
Check the trouble
symptoms.
Check the following connectors:
C-32, C-08.
C-32
(2) NG
OK
Check the trouble
symptoms.
Measure at the A/C-ECU connector C-32.
DDisconnect the connector and measure at the harness
side.
DIgnition switch: ON
(1) Voltage between terminal 10 and body earth.
Voltage between terminal 7 and body earth.
OK :Battery voltage
(2) Continuity between terminals 12 and body earth.
Continuity between terminals 3 and body earth.
OK :Continuity(1) NGCheck the following connectors:C-32, C-209, C-210
OK
Check the trouble
symptoms.

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-4
Inspection procedure 2
Blower motor not working
Probable cause
If the blower motor does not work, the blower motor circuit system may be
defective.DBlower motor fault
DHarness or connector fault
DA/C-ECU fault
NG
Replace
NG
Check the harness between the Ignition switch (IG2) and the
blower relay, and between fusible link No. 1 and the blower
relay, and repair if necessary.
OK
Check the trouble
symptoms.
NG
Repair
NG
Replace
OK
Check the resister. (Refer to P.55-32.)
NG
Replace
OK
Check the blower switch. (Refer to P.55-25.)
NG
Replace
OK
Check the blower relay. (Refer to P.55-22.)
NG
Repair
NG
Check the harness between the blower relay and body earth,
and repair if necessary.
OK
Check the trouble
symptoms.
Check the following connectors:
C-215, C-213.
C-215, C-213, C-08
(3) NG
OK
OK
(1) NG
Check the following connectors:C-215, C-210.
NG
Check the harness between the Ignition switch (IG2) and the
blower relay, and between fusible link No. 1 and the blower
relay, and repair if necessary.
OK
Check the trouble
symptoms.Repair
Check the following connectors:
C-215, C-211, C-132
C-215, C-11, C-35, C-132
(2) NG
Measure at the blower relay connector C-215.
DDisconnect the connector and measure at the harness
side.
DIgnition switch: ON
(1) Voltage between terminals 1 and body earth
OK :Battery voltage
(2) Voltage between terminals 5 and body earth
OK :Battery voltage
(3) Continuity between terminal 3 and body earth
OK :Continuity
To the next page
Check the blower motor. (Refer to P.55-32.)

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-5
NG
Repair
NG
Repair
NG
Check the harness between the blower motor and the body
harness, and repair if necessary.
OK
Check the trouble
symptoms.
NG
Check the harness between the blower motor and the blower
relay, and repair if necessary.
OK
Check the trouble
symptoms.
Check the following connector:C-14.
(2) NG
OK
Check the trouble
symptoms.
NG
Check the harness between the blower switch and the
register, and between the register and blower motor, and
repair if necessary.
NG
Repair
OK
Measure at the blower motor connector C-14.
DDisconnect the connector and measure at the harness
side.
DIgnition switch: ON
DBlower switch position:4
(1) Voltage between terminal 1 and body earth
OK :Battery voltage
(2) Continuity between terminal 2 and body earth
OK :Continuity(1) NG
From the previous page
Check the following connectors:C-131, C-16, C-14.
Check the following connectors:C-215, C-210, C-131, C-14.
Inspection procedure 3
Air cannot be switched between inside and outside.
Probable cause
If the air cannot be switched between the inside and outside even though the
inside/outside switch is ON, the inside/outside changeover damper motor system
may be defective.DInside/outside air changeover damper motor fault
DHarness or connector fault
DA/C-ECU fault
NG
Replace
NG
Repair
OK
OK
Check the following connectors:C-10, C-107, C-32.
NG
Check the harness between the Ignition switch (IG2) and the
inside/outside air changeover damper motor, and repair if
necessary.
OK
Check the trouble
symptoms.
NG
Repair
OK
Measure at the inside/outside air changeover damper motor
connector C-10.
DDisconnect the connector and measure at the harness
side.
DIgnition switch: ON
DVoltage between terminal 7 and body earth.
OK :Battery voltageNGCheck the following connectors:C-10, C-107, C-102, C-209,
C-210.
Check the inside/outside air changeover damper motor (Refer
to P.55-32.).
NG
Repair
OK
Replace manual air conditioner control panel (A/C-ECU).
NG
Check the trouble
symptoms.
Check the harness between the inside/outside air changeover
damper motor and the A/C-ECU.

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-6
Inspection procedure 4
Rear defogger not working
Probable cause
If the rear window defogger does not work even though the rear defogger switch
is ON (a 20-minute timer operates), the defogger relay system may be defective.DDefogger relay fault
DHarness or connector fault
DA/C-ECU fault
NG
Check the harness between the ignition switch (IG2) and the
defogger relay, and repair if necessary.
NG
Repair
Replace manual air conditioner control panel (A/C-ECU).
OK
OK
Check the trouble
symptoms.
NG
Check the following connectors:C-214, C-213, C-32.
OK
Check the trouble
symptoms.
NG
Replace
NG
Repair
NG
Check the harness between fusible link No. 1 and defogger
relay, and repair if necessary.
OK
Check the trouble
symptoms.
Check the following connectors:
C-214, C-211, C-132.
C-214, C-211, C-35, C-132
(2) NG
NG
Repair
NG
Check the harness between the defogger relay and the choke
coil, and repair if necessary.
OK
Check the trouble
symptoms.
Check the following connectors:
C-214, C-216, F-19.
C-214, C-217, F-19
NG
Repair
Check the following connectors:F-06.
OK
OK
Measure at the choke coil connector F-19.
DDisconnect the connector and measure at the harness
side.
DIgnition switch: ON
DVoltage between terminal 1 and body earth.
OK :Battery voltageNG
OK
Measure at the defogger relay connector C-214.
DDisconnect the connector and measure at the junction box
side.
DIgnition switch: ON
(1) Voltage between terminal 1 and body earth.
OK :Battery voltage
(2) Continuity between terminal 5 and body earth.
OK :Battery voltage(1) NGCheck the following connectors:C-214, C-210.
OK
Check the trouble
symptoms.
NG
RepairNG
Check the harness between body earth and defogger.
NG
RepairNG
Check harness between the defogger relay and A/C-ECU.
OK
Replace choke coil.
Check the defogger (Refer to Group 54A – Defogger.).

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-7
Inspection procedure 5
Cold air not coming out from the air outlet
Probable cause
If cold air does not come out from the air outlet, the amount of refrigerant may
be inappropriate or the compressor circuit system may be defective.DRefrigerant line fault
DAmount of refrigerant fault
DCompressor fault
DCompressor relay fault
DDual pressure switch fault
DEngine-ECUfault
DA/C-ECU fault
OK
NG
Repair
NG
Check the harness between the A/C compressor relay and the
ignition switch (IG2), and repair if necessary.
OK
Check the trouble
symptoms.
Check the following connectors:
C-12X, C-130, C-102, C-209, C-210
C-12X, C-128, D-102, C-209, C-210NG
Repair
Check the following connectors:
C-12X, A-13, A-47.
C-12X, A-136, A-47.
OK
OK
Check the trouble
symptoms.
NG
OK
NG
Replace
OK
OK
OK
NG
Check the harness between the battery and the A/C
compressor relay., and repair if necessary.
OK
Check the trouble
symptoms.
Check the following connectors:
B-12X, A-43
B-12X, C-136.(1) NG
RepairNG
(2) NG
OK
Check the dual pressure switch.
OK
NG
Repair
Check the harness between the A/Compressor relay and the
A/Compressor.
NG
Repair
Check the following connectors:B-12X, C-126.
OK
Check the trouble
symptoms.
NG
OKNG
Repair
Check the harness between the A/Compressor relay and the
Engine-ECU.
To the next page
Check refrigerant for leakage.
NG
Replace
NG
Replace
NG
NG
Replace
Check the amount of refrigerant.
Check the compressor relay.
Check the compressor magnetic clutch.
Check the refrigerant temperature switch.
Measure at the compressor relay B-12X.
DDisconnect the connector and measure at the harness
side.
DIgnition switch: ON
(1) Voltage between terminal 1 and body earth.
OK :Battery voltage
(2) Continuity between terminal 2 and body earth.
OK :Battery voltage
Refer to Inspection procedure 6 magnet clutch not working
normally.

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-8
Repair
Repair
NG
Replace the A/C-ECU .
Replace the Engine-ECU .
NG
Repair
Check the following connectors:
A-36, C-111, C-130, C-122, C-32.
A-36, C-111, C-128, C-122, C-32.
OK
Check the trouble
symptoms.
NG
OKNG
Check the harness between the dual pressure switch and the
Engine-ECU.
Check the following connectors:C-32, C-111, A-36.
OK
NG
OKNG
Check the harness between the dual pressure switch and the
A/C-ECU.
From the previous page
Check the trouble
symptoms.RepairNG
Inspection procedure 6
Magnet clutch not working normally
Probable cause
If the magnet clutch does not work normally, the field core or the compressor
may be defective.DCompressor fault
DField core fault
Replace the field core.
Is not the Compressor locked ?NGReplace the compressor and field core.
No

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-9
Inspection procedure 7
Condenser fan not working at all
Probable cause
If the condenser fan does not work at all, the condenser fan circuit system may
be defective.DCondenser fan motor fault
DHarness or connector fault
DEngine-ECU fault
NG
Check the harness betweenthe condenser fan relay (LO) and
the ignition switch (IG2) , and repair if necessary.
OK
Check the trouble
symptoms.
NG
Repair
NG
Replace
OK
Check the condenser fan motor. (Refer to P.55-40.)
NGCheck the following connectors:A-06X, C-135, C-102,
C-209, C-210.
OK
Measure at the condenser fan relay (LO) A-06X.
DDisconnect the connector and measure at the harness
side.
DIgnition switch: ON
DVoltage between terminal 2 and body earth.
OK :Battery voltage
NG
Check the harness betweenthe condenser fan motor and body
earth, and repair if necessary.
OK
Check the trouble
symptoms.Repair
NGCheck the following connectors:A-46.
NG
OK
Measure at the condenser fan motor A-46.
DDisconnect the connector and measure at the harness
side.
DContinuity between terminal 2 and body earth
OK :Continuity
NG
OK
Check the trouble
symptoms.RepairNG
Check the following connectors:
C-122, A-43, A-06X.
C-122, C-136, A-06X
Replace the Engine-ECU.
OK
RepairNG
Check the harness betweenthe condenser fan relay (LO) and
the Engine-ECU.

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-10
Inspection procedure 8
Condenser fan not working only for LO
Probable cause
If the condenser fan does not work only for LO, the condenser fan circuit
system or the condenser fan relay (LO) circuit system may be defective.DCondenser fan motor fault
DCondenser fan relay (LO) fault
DHarness or connector fault
DEngine-ECU fault
NG
Check the harness betweenthe condenser fan relay (LO) and
the ignition switch (IG2), and repair if necessary.
OK
Check the trouble
symptoms.
NG
Repair
NG
Replace
OK
Check the condenser fan motor. (Refer to P.55-40.)
Check the following connectors:A-06X, C-135, C-102,
C-209, C-210.
OK
NG
OK
Check the trouble
symptoms.Repair
Check the following connectors:A-06X.
NG
NG
OK
Check the trouble
symptoms.RepairNG
Check the following connectors:
A-06X, A-43, C-122.
A-06X, C-136, C-122.
Replace the Engine-ECU .
OK
RepairNG
Check the harness betweenthe condenser fan relay (LO) and
the Engine-ECU.
(2) NG
Measure at the condenser fan relay (LO) A-06X.
DDisconnect the connector and measure at the junction box
side.
DIgnition switch: ON
(1) Voltage between terminal 2 and body earth.
OK :Battery voltage
(2) Voltage between terminal 4 and body earth.
OK :Battery voltage(1) NG
NG
Replace
OK
Check the condenser fan relay (LO) (Refer to P.55-23.)
NG
OK
Check the trouble
symptoms.Repair
Check the following connectors:A-06X, A-45.
OK
Check the harness betweenthe condenser fan relay (LO) and
the condenser fan motor, and repair if necessary.
Check the harness betweenthe condenser fan relay (LO) and
the battery, and repair if necessary.

HEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-11
Inspection procedure 9
Condenser fan not working only for HI
Probable cause
If the condenser fan does not work only for HI, the condenser fan circuit system
or the condenser fan relay (HI) circuit system may be defective.DCondenser fan motor fault
DCondenser fan relay (HI) fault
DHarness or connector fault
DEngine-ECU fault
NG
Check the harness between the condenser fan relay (HI) and
the Ignition switch (IG2), and repair if necessary.
OK
Check the trouble
symptoms.
NG
Repair
NG
Replace
OK
Check the condenser fan motor. (Refer to P.55-40.)
Check the following connectors:A-07X, C-135, C-102,
C-209, C-210.
OK
NG
Check the harness betweenthe condenser fan relay
(HI) and the fusible link (2)
, and betweenthe condenser fan relay (HI) and the
battery, and repair if necessary.
OK
Check the trouble
symptoms.Repair
Check the following connectors:A-07
NG
NG
OK
Check the trouble
symptoms.RepairNG
Check the following connectors:
A-07X, A-43, C-122.
A-07X, C-136,C-122
Replace the Engine-ECU.
OK
RepairNG
Check the harness betweenthe condenser fan relay (HI) and
the Engine-ECU.
(2) NG
Measure at the condenser fan relay (HI) A-07X.
DDisconnect the connector and measure at the junction box
side.
DIgnition switch: ON
(1) Voltage between terminal 2 and body earth.
OK :Battery voltage
(2) Voltage between terminal 4 and body earth.
OK :Battery voltage(1) NG
NG
Replace
OK
Check the condenser fan relay (HI) . (Refer to P.55-23.)
NG
Check the harness betweenthe condenser fan relay (HI) and
the condenser fan motor, and repair if necessary.
OK
Check the trouble
symptoms.Repair
Check the following connectors:A-07X, A-45.
OK

HEATER, AIR CONDITIONER AND VENTILATION-TroubleshootingHEATER, AIR CONDITIONER AND VENTILATION-Troubleshooting55-12
CHECK AT THE ENGINE-ECU TERMINAL
Terminal no.Check itemCheck whenNormal state
21Fan controller outputRadiator fan: ON0 - 0.3 Vp
Radiator fan: OFF0.7 V or more
22A/C compressor outputA/C compressor relay: OFF0Vpp
A/C compressor relay: ONBattery voltage
or temporarily
6V or more→
1V or less
24A/C-ECU input (A/C2)At A/C low loadBattery voltage
32Condenser fan motor relay (HI)Fan: OFF(engine coolant temperature:90_C
or lower)Battery voltage
Fan: ON(engine coolant tempera-
ture:105_C or lower)1V or more
34Condenser fan motor relay (LOW)Fan: OFF(engine coolant temperature:90_C
or lower)Battery voltage
Fan: ON(engine coolant tempera-
ture:105_C or lower)1V or more
45A/C-ECU input (A/C1)A/C ON (When dual pressure switch is ON)Battery voltage
CHECK AT THE A/C-ECU TERMINAL
Termi-
nal no.Check itemCheck whenNormal state
1Rear defogger switchDefogger switch: ON0Vgg
Defogger switch: OFFBattery voltage
2Inside/outside air changeover
dt(tidi)
When damper moved to inside circulation position0Vg
damper motor (outside air)When damper moved to outside air induction
positionBattery voltage
3Inside/outside air changeover
dt(i idi)
When damper moved to inside circulation positionBattery voltageg
damper motor (inside air)When damper moved to outside air induction
position0V
4Engine-ECU output (A/C1)When A/C OFF0Vgp()
A/C switch: ON, blower: ON (room temperature)Battery voltage
5Engine-ECU output (A/C2)At A/C low loadBattery voltagegp()
At A/C high load0V
6Illumination power supplyLighting switches: ONBattery voltage
7---
8Blower switch (LO)Blower switch: LOBattery voltage