Subaru 2009 IMPREZA Service Manual page 720

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK ACCELERATOR PEDAL POSITION
SENSOR OUTPUT.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
Main accelerator pedal position sensor
signal
(B135) No. 23 (+) — Chassis ground (–):
Sub accelerator pedal position sensor
signal
(B135) No. 31 (+) — Chassis ground (–):
2 CHECK ACCELERATOR PEDAL POSITION
SENSOR OUTPUT.
1) Measure the voltage between accelerator
pedal position sensor connector and chassis
ground.
Connector & terminal
(B315) No. 6 (+) — Chassis ground (–):
(B315) No. 3 (+) — Chassis ground (–):
3 CHECK HARNESS BETWEEN ECM AND AC-
CELERATOR PEDAL POSITION SENSOR
CONNECTOR.
Measure the resistance of harness between
accelerator pedal position sensor connector
and chassis ground.
Connector & terminal
(B315) No. 5 — Chassis ground:
(B315) No. 2 — Chassis ground:
Check
Is the difference in measured
values for the main accelerator
pedal position sensor signal
and the sub accelerator pedal
position sensor signal 0 V?
Is the difference in measured
values for the main accelerator
pedal position sensor signal
and the sub accelerator pedal
position sensor signal 0 V?
Is the resistance less than 5 ? Repair the poor
EN(H4SO)(diag)-303
ENGINE (DIAGNOSTICS)
Yes No
Go to step 3. Go to step 2.
Replace the accel- Repair the harness
erator pedal. <Ref. and connector.
to SP(H4SO)-4,
NOTE:
Accelerator
In this case, repair
Pedal.>
the following item:
• Open circuit in
harness between
ECM and acceler-
ator pedal position
sensor connector
• Short circuit to
ground in harness
between ECM and
accelerator pedal
position
connector
• Poor contact of
coupling connector
Repair the harness
contact of ECM and connector.
connector.
NOTE:
In this case, repair
the following item:
• Open circuit in
harness between
ECM and acceler-
ator pedal position
sensor connector
• Open circuit of
harness between
ECM and engine
ground
• Poor contact of
ECM connector
• Poor contact of
coupling connector
sensor