Mitsubishi Space Star. Manual - part 79

DIESEL FUEL – 

Troubleshooting

13D-15

Code No. 18 Air flow sensor system

Probable cause

Range of Check



Ignition switch: ON

Set Conditions



Sensor output voltage is 100 mV or less for 1.5 seconds

or



Sensor output voltage is 1,200 mV or more for 1.5 seconds

Range of Check



Engine speed : 700 r/min or more

Set Conditions



Sensor output is 10 kg/h or less for 1 second



Malfunction of the air flow sensor



Improper connector contact, open circuit or
short-circuited harness wire of the air flow sensor
circuit



Malfunction of the engine-ECU

(2) NG

Repair

Measure at the air flow sensor connector A-73.



Disconnect the connector and measure at the harness
side.

(1) Voltage between 4 and earth (Ignition switch: ON)

OK: System voltage

(2) Voltage between 3 and earth (Ignition switch: ON)

OK: 4.8  – 5.2 V

(3) Continuity between 6 and earth

OK: Continuity

(1) NG

OK

Repair

NG

Check the following connectors: A-73, A-121

NG

Repair

NG

NG

OK

Check the harness wire between the air flow sensor and the
engine-ECU (sensor signal line).

OK

Check trouble symptom.

Check the harness wire between the air flow sensor and the
main relay, and repair if necessary.

Check the following connectors: A-120, A-121

OK

NG

Check the harness wire between the air flow sensor and the
engine-ECU.

Repair

OK

NG

Replace the engine-ECU.

NG

Check trouble symptom.

NG

Replace the engine-ECU.

OK

NG

INTERMITTENT MALFUNCTIONS
Refer to GROUP 00 – Points to Note for Intermittent
Malfunctions*

MUT-

II

 Data list

08 Air flow sensor (Refer to P.13D-46.)

(3) NG

Check the harness wire between the air flow sensor and the
earth, and repair if necessary.

*:

Refer to ’99 SPACE STAR Workshop Manual (Pub. No. CMXE99E1)

DIESEL FUEL – 

Troubleshooting

13D-16

Code No. 19 Engine coolant temperature sensor system

Probable cause

Range of Check



Ignition switch: ON

Set Conditions



Sensor output voltage is 100 mV or less for 1 second

or



Sensor output voltage is 4,900 mV or more for 1 second



Malfunction of the engine coolant temperature
sensor



Improper connector contact, open circuit or
short-circuited harness wire of the engine coolant
temperature sensor circuit



Malfunction of the engine-ECU

NG

Check the following connector: A-121

Replace

NG

OK

Measure at the engine coolant temperature sensor connector A-76.



Disconnect the connector and measure at the harness
side.



Voltage between 3 and earth (Ignition switch: ON)
OK: 4.8  – 5.2 V



Continuity between 2 and earth
OK: Continuity

OK

NG

Check the harness wire between the engine coolant
temperature sensor and the engine-ECU.

Repair

NG

Check the following connector: A-76

OK

Check the engine coolant temperature sensor (Refer to
P.13D-52.)

OK

Check trouble symptom.

Repair

NG

Replace the engine-ECU.

OK

INTERMITTENT MALFUNCTIONS
Refer to GROUP 00 – Points to Note for Intermittent
Malfunctions*

MUT-

II

 Data list

01 Engine coolant temperature sensor (Refer to P.13D-46.)

OK

Repair

NG

Replace the engine-ECU.

NG

Check trouble symptom.

NG

*:

Refer to ’99 SPACE STAR Workshop Manual (Pub. No. CMXE99E1)

DIESEL FUEL – 

Troubleshooting

13D-17

Code No. 21 Fuel temperature sensor system

Probable cause

Range of Check



Ignition switch: ON

Set Conditions



Sensor output voltage is 100 mV or less for 1 second

or



Sensor output voltage is 4,900 mV or more for 1 second



Malfunction of the fuel temperature sensor



Improper connector contact, open circuit or
short-circuited harness wire of the fuel
temperature sensor circuit



Malfunction of the engine-ECU

NG

Check the following connector: A-121

Replace

NG

OK

Measure at the fuel temperature sensor connector A-117.



Disconnect the connector and measure at the harness
side.



Voltage between 1 and earth (Ignition switch: ON)
OK: 4.8  – 5.2 V



Continuity between 2 and earth
OK: Continuity

OK

NG

Check the harness wire between the fuel temperature sensor
and the engine-ECU.

Repair

NG

Check the following connector: A-117

OK

Check the fuel temperature sensor (Refer to P.13D-53.)

OK

Check trouble symptom.

Repair

NG

Replace the engine-ECU.

OK

INTERMITTENT MALFUNCTIONS
Refer to GROUP 00 – Points to Note for Intermittent
Malfunctions*

MUT-

II

 Data list

02 Fuel temperature sensor (Refer to P.13D-46.)

OK

Repair

NG

Replace the engine-ECU.

NG

Check trouble symptom.

NG

*:

Refer to ’99 SPACE STAR Workshop Manual (Pub. No. CMXE99E1)

DIESEL FUEL – 

Troubleshooting

13D-18

Code No. 22 Intake air temperature sensor system

Probable cause

Range of Check



Ignition switch: ON

Set Conditions



Sensor output voltage is 100 mV or less for 1 second

or



Sensor output voltage is 4,850 mV or more for 1 second



Malfunction of the intake air temperature sensor



Improper connector contact, open circuit or
short-circuited harness wire of the intake air
temperature sensor circuit



Malfunction of the engine-ECU

NG

Check the following connectors: A-120, A-121

Replace

NG

OK

Measure at the air flow sensor connector A-73



Disconnect the connector and measure at the harness
side.



Voltage between 1 and earth (Ignition switch: ON)
OK: 4.8  – 5.2 V



Continuity between 2 and earth
OK: Continuity

OK

NG

Check the harness wire between the intake air temperature
sensor and the engine-ECU.

Repair

NG

Check the following connector: A-73

OK

Check the intake air temperature sensor (Refer to P.13D-52.)

OK

Check trouble symptom.

Repair

NG

Replace the engine-ECU.

OK

INTERMITTENT MALFUNCTIONS
Refer to GROUP 00 – Points to Note for Intermittent
Malfunctions*

MUT-

II

 Data list

03 Intake air temperature sensor (Refer to P.13D-46.)

OK

Repair

NG

Replace the engine-ECU.

NG

Check trouble symptom.

NG

*:

Refer to ’99 SPACE STAR Workshop Manual (Pub. No. CMXE99E1)