Mitsubishi MOTORS Space Runner 1999 Workshop Manual Supplement page 392

Code No.78 Accelerator pedal position sensor (1st
channel) system
Range of check
Accelerator pedal position sensor (2nd channel) system is normal.
Communication between the engine-ECU and throttle valve controller is normal.
Set conditions
Output voltage of accelerator position sensor (1st channel) system is 0.2 V or
less for one second.
or
Output voltage of the accelerator pedal position sensor (2nd channel) is 2.5
V or less, and (1st channel) output voltage of the accelerator pedal position
sensor is 4.5 V or more for one second.
or
Difference between the accelerator pedal position sensor (1st and 2nd channels)
output voltages exceeds 1.0 V (i.e. when the throttle valve opening angle changes
slightly).
or
Although the accelerator pedal position switch is on, 1st-channel output voltage
of the accelerator pedal position sensor exceeds 1.1 V for one second.
MUT-II Data list
26 Accelerator pedal position switch
(P.13A-76.)
OK
Check the accelerator pedal position
sensor (1st channel). (Refer to P.13A-
107.)
OK
Measure at the accelerator pedal posi-
tion sensor (1st channel) connector
A-84.
Disconnect the connector, and
measure at the harness side.
Voltage between terminal 2 and
earth
(Ignition switch: ON)
OK: 4.8 – 5.2 V
Continuity between terminal 5 and
earth
OK: Continuity
OK
Measure at the engine-ECU B-31.
Connect the connector.
Voltage between terminal 87 and
earth
(Ignition switch: ON)
OK: 0.9 – 1.2 V
(Accelerator pedal: fully re-
leased)
4 V or more
(Accelerator pedal: fully de-
pressed)
OK
MUT-II Data list
78 Accelerator pedal position sensor
(2nd channel). (Refer to P.13A-78.)
OK
Replace the engine-ECU.
GDI –
Troubleshooting
NG
Check the accelerator pedal position
switch system. (Refer to P.13A-67, IN-
SPECTION PROCEDURE 28.)
NG
Replace the accelerator pedal position
sensor assembly.
NG
Check the following connectors:
B-30, B-31
Check trouble symptom.
NG
Check the following connector:
A-84
Check trouble symptom.
NG
Check the accelerator pedal position
sensor (2nd channel) system. (Refer
to P.13A-32, INSPECTION PROCE-
DURE FOR DIAGNOSIS CODE 77.)
Probable cause
Malfunction of the accelerator pedal position sensor
(1st channel)
Open circuit or short-circuited harness wire in the
accelerator pedal position sensor (1st channel)
system, or poor connector contact
ON-seizure of the accelerator pedal position switch
Malfunction of the throttle valve controller
Malfunction of the engine-ECU
NG
OK
NG
NG
OK
NG
13A-33
Repair
Check the harness wire between the
accelerator pedal position sensor (1st
channel) and engine-ECU.
OK
NG
Repair
Replace the engine-ECU.
Repair
Check the harness wire between the
accelerator pedal position sensor (1st
channel) and engine-ECU.
OK
NG
Repair
Adjust the accelerator pedal position
sensor (1t channel). (Refer to P.13A-
97.)
Check trouble symptom.
NG
Replace the engine-ECU.