Mitsubishi Outlander (2013+). Manual - part 317

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-149

STEP 13. Check harness between OSS-ECU 
connector terminal IG1 and ETACS-ECU 
connector terminal IG1.

• Check power supply line for open/short circuit.

Q: Is the check result normal?

YES : 

Perform troubleshooting of OSS System 

(Refer to GROUP 42B 

− Troubleshooting − 

Trouble Symptom Chart ).

NO : 

Repair or replace the connector, or repair 
the damaged harness wire.

STEP 14. Continuity check on ETACS-ECU 
connectors

• Disconnect connectors, and measure at the 

ETACS-ECU side.

• Continuity test between terminal IG1 and IGN.

NOTE: Connect the (+) side of circuit tester to termi-
nal IGN.

OK: Continuity

Q: Is the check result normal?

YES : 

Check and repair harness between 

ETACS-ECU connector terminal IGN and 
engine-ECU connector terminal IGN.

• Check signal line for open/short 

circuit.

NO : 

Replace the ETACS-ECU.

STEP 15. Check harness between ignition switch 
connector terminal IG1 line and ETACS-ECU 
connector IG1.

• Check signal line for damage.

Q: Is the check result normal?

YES : 

Go to Step 17.

NO : 

Repair or replace the connector, or repair 
the damaged harness wire.

STEP 16. Check harness between OSS-ECU 
connector terminal IG1 and ETACS-ECU 
connector terminal IG1.

• Check signal line for damage.

Q: Is the check result normal?

YES : 

Go to Step 17.

NO : 

Repair or replace the connector, or repair 
the damaged harness wire.

STEP 17. Continuity check on ETACS-ECU 
connectors

• Disconnect connectors, and measure at the 

ETACS-ECU side.

• Continuity test between terminal IG1 and IGN.

NOTE: Connect the (+) side of circuit tester to termi-
nal IGN.

OK: Continuity

Q: Is the check result normal?

YES : 

Go to Step 18.

NO : 

Replace the ETACS-ECU.

STEP 18. Check harness between ETACS-ECU 
connector terminal IGN and engine-ECU 
connector terminal IGN.

• Check signal line for damage.

Q: Is the check result normal?

YES : 

Go to Step 19.

NO : 

Repair or replace the connector, or repair 
the damaged harness wire.

STEP 19. Check harness between engine-ECU 
connector terminal GNDB, GNDE and body earth.

• Check earthing line for open circuit and damage.

Q: Is the check result normal?

YES : 

Replace the engine-ECU.

NO : 

Repair the damaged harness wire.

Inspection Procedure 20: Fuel Pump System

OPERATION

• The fuel pump drive power is supplied from 

engine control relay to fuel pump relay 
(ETACS-ECU connector terminal F/PB) in the 
ETACS-ECU.

• The battery voltage is applied by the ignition 

switch <Vehicles without KOS> or the OSS-ECU 
<Vehicles with KOS> to the fuel pump relay coil 
(ETACS-ECU connector terminal IG1) in the 
ETACS-ECU. The engine-ECU turns on the relay 
by turning ON the power transistor in the unit so 
as to conduct power to the fuel pump relay coil 
(via the ETACS-ECU connector terminal FP/R).

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-150

• When the fuel pump relay is turned ON, the bat-

tery voltage will be supplied from the fuel pump 
relay (ETACS-ECU connector terminal F/PB) to 
the fuel pump connector terminal.

FUNCTION

• When the ignition switch ON signal is inputted 

into the engine-ECU, the engine-ECU turns ON 
the fuel pump relay. This causes the battery volt-
age to be supplied to the fuel pump.

PROBABLE CAUSES

• Failed fuel pump relay in the ETACS-ECU

• Failed fuel pump

• Open/short circuit or harness damage in fuel 

pump drive circuit, or loose connector contact.

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: ETACS-ECU 
connectors

Q: Are the check results normal?

YES : 

Go to Step 2.

NO : 

Repair or replace the connector.

STEP 2. Check fuel pump relay.

• Fuel pump relay continuity check (Refer to 

P.13A-184

).

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Replace the ETACS-ECU.

STEP 3. Perform voltage measurement at 
engine-ECU connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: "ON"

• Voltage between terminal FP/R and body earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair or replace the connector, or check 

and repair harness between engine-ECU 
connector terminal FP/R and ETACS-ECU 
connector terminal FP/R.

• Check power supply line for 

open/short circuit.

STEP 4. Perform voltage measurement at 
ETACS-ECU connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: "ON"

• Voltage between terminal F/PB and body earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Go to Step 5.

STEP 5. Connector check: Engine control relay 
connector

Q: Is the check result normal?

YES : 

Check and repair harness between engine 

control relay connector terminal and 
ETACS-ECU connector terminal F/PB.

• Check power supply line for 

open/short circuit.

NO : 

Repair or replace the connector.

STEP 6. Check fuel pump operations.

• Fuel pump connector check.

• Fuel tank pump operation check (Refer to 

P.13A-182

).

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Repair or replace the connector, or replace 
the fuel tank pump and gauge assembly.

STEP 7. Perform resistance measurement at fuel 
pump connector.

• Disconnect connector, and measure at harness 

side.

• Resistance between terminal earth line and body 

earth.

OK: Continuity (2 

Ω or less)

Q: Is the check result normal?

YES : 

Go to Step 8.

NO : 

Check and repair harness between fuel 

pump connector terminal earth line and 
body earth.

• Check earthing line for open circuit 

and damage.

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-151

STEP 8. Perform voltage measurement at fuel 
pump connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: "ON"

• Voltage between terminal power supply line and 

body earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 10.

NO : 

Go to Step 9.

STEP 9. Check harness between ETACS-ECU 
connector terminal F/P and fuel pump connector.

• Check power supply line for open/short circuit.

Q: Is the check result normal?

YES : 

Check and repair harness between 

engine-ECU connector terminal FP/R and 
ETACS-ECU connector terminal FP/R. 

• Check power supply line for damage.

NO : 

Repair the damaged harness wire.

STEP 10. Check harness between engine control 
relay connector terminal and ETACS-ECU 
connector terminal F/PB.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 11.

NO : 

Repair or replace the connector, or repair 
the damaged harness wire.

STEP 11. Check harness between ETACS-ECU 
connector terminal F/P and fuel pump connector 
terminal.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 12.

NO : 

Repair the damaged harness wire.

STEP 12. M.U.T.-III actuator test

• Item 9: Fuel pump

OK: Operating sound of fuel pump can be 
heard.

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunctions 
).

NO : 

Replace the engine-ECU.

Inspection Procedure 21: A/C Compressor Relay System

OPERATION

• Battery voltage is applied to the A/C compressor 

relay connector terminal.

• Engine-ECU connector terminal AC/R applies 

current to the A/C compressor relay coil by turn-
ing ON the power transistor in the unit in order to 
turn the relay ON.

• When the A/C compressor relay turns ON, bat-

tery voltage is supplied by the A/C compressor 
relay connector terminal to the A/C compressor 
connector terminal.

FUNCTION

• When the A/C switch ON signal is input into the 

engine-ECU, the engine-ECU turns ON the A/C 
compressor relay. This causes battery voltage to 
be supplied to the A/C compressor assembly and 
the A/C compressor clutch actuates.

PROBABLE CAUSES

• Failed A/C compressor relay

• Failed A/C compressor assembly

• Open/short circuit or harness damage in A/C 

compressor relay circuit, or loose connector con-
tact.

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check A/C compressor relay itself.

• A/C compressor relay connector check.

• Check A/C compressor relay itself (Refer to 

GROUP 55 

− On-vehicle Service − Relay Check 

).

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair or replace the connector or replace 
the A/C compressor relay.

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-152

STEP 2. Perform voltage measurement at A/C 
compressor relay.

• Disconnect relay, and measure at relay box side.

• Voltage between terminal power supply lines and 

body earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Check and repair harness between battery 

and A/C compressor relay connector 
terminals.

• Check power supply line for 

open/short circuit.

STEP 3. Check harness between battery and A/C 
compressor relay connector terminal.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair the damaged harness wire.

STEP 4. Perform voltage measurement at 
engine-ECU connector.

• Disconnect connector, and measure at harness 

side.

• Voltage between terminal AC/R and body earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Repair or replace the connector, or check 

and repair harness between A/C 
compressor relay connector terminal and 
engine-ECU connector terminal AC/R.

• Check signal line for open/short 

circuit.

STEP 5. Check harness between A/C compressor 
relay connector terminal and engine-ECU 
connector terminal AC/R.

• Check signal line for damage.

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Repair the damaged harness wire.

STEP 6. Check harness between A/C compressor 
relay connector terminal and A/C compressor 
assembly connector terminal.

• Check power supply line for open/short circuit 

and damage.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Repair or replace the connector, or repair 
the damaged harness wire.

STEP 7. Check A/C compressor clutch operating 
conditions.

• Disconnect engine-ECU connector, and short-cir-

cuit terminal AC/R to the body earth.

OK: A/C compressor clutch operates.

Q: Is the check result normal?

YES : 

Replace the engine-ECU.

NO : 

Replace the A/C compressor assembly.

Inspection Procedure 22: Ignition Circuit System

OPERATION

• The battery voltage is applied from the engine 

control relay connector terminal to the ignition coil 
connector terminal and is earthed to the vehicle 
body via the ignition coil connector terminal No. 
1.

• A power voltage of 12 V is applied to the ignition 

coil connector terminal from the engine-ECU con-
nector terminal CIL1, CIL2, CIL3 and CIL4).

FUNCTION

• When the engine-ECU turn the power transistor 

in the unit to OFF, the battery voltage is applied to 
the power transistor in the ignition coil, resulting 
that the power transistor is ON. And, when the 
engine-ECU turns the power transistor in the unit 
to ON, the power transistor in the ignition coil will 
be turned OFF.

• When the power transistor in the ignition coil is 

turned to ON with any signal from the 
engine-ECU, the primary voltage will be applied 
through the ignition coil. When the power transis-

tor in the ignition coil is turned OFF, the primary 
current is blocked and high voltage is generated 
in the secondary coil.