Mitsubishi MOTORS Space Runner 1999 Workshop Manual Supplement page 89

13D-24
Code No. 59 Oxygen sensor (rear) system
Range of Check
D 3 minutes have passed after engine was started.
D Engine coolant temperature is approx. 80_C or more.
D Idle position switch: OFF
D The throttle position sensor output voltage is 4.1 V or more.
D Open loop control in operation
D 20 seconds have passed after deceleration finished.
Set conditions
D The oxygen sensor (rear) output voltage is 0.1 V or less.
D The difference in the maximum and minimum values for the oxygen sensor (rear)
output voltage is 0.08 V or less.
D The oxygen sensor (rear) output voltage is 0.5 V or more.
D The above conditions continue for a continuous period of 5 seconds.
Check the oxygen sensor (rear). (Refer to P.13D-88.)
OK
Measure at the oxygen sensor (rear) connector C-29.
D Disconnect the connector, and measure at the
harness side.
1. Voltage between 3 and earth (Ignition switch: ON)
OK: System voltage
2. Continuity between 2 and earth
OK: Continuity
3. Continuity between 4 and earth
OK: Continuity
OK
Check the following connectors:
B-51 <M/T>, B-111 <A/T>, B-14, B-49
OK
Check trouble symptom.
NG
Check the harness wire between the engine-ECU <M/T>
or engine-A/T-ECU <A/T> and the oxygen sensor (rear)
connector.
OK
Replace the oxygen sensor (rear).
Check trouble symptom.
NG
Replace the engine-ECU <M/T> or engine-A/T-ECU
<A/T>.
MPI -
Troubleshooting
NG
Replace
1. NG
2. NG
3. NG
NG
Repair
NG
Repair
Probable cause
D Malfunction of the oxygen sensor (rear)
D Improper connector contact,
short-circuited harness wire
D Malfunction of the engine-ECU
engine-A/T-ECU <A/T>
Check the following connector:
B-14, B-49
OK
Check trouble symptom.
NG
Check the harness wire between the
oxygen sensor (rear) and the control
relay connector, and repair if necessary.
Check the following connector:
B-51 <M/T>, B-111 <A/T>, B-14, B-49
OK
Check trouble symptom.
NG
Check the harness wire between the
engine-ECU <M/T> or engine-A/T-ECU
<A/T> and the oxygen sensor (rear)
connector.
OK
Replace the engine-ECU <M/T> or en-
gine-A/T-ECU <A/T>.
Check the harness wire between the
oxygen sensor (rear) and the earth, and
repair if necessary.
open circuit or
<M/T> or
NG
Repair
NG
Repair
NG
Repair