Subaru 2009 IMPREZA Service Manual page 1552

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK HARNESS BETWEEN ECM AND AC-
CELERATOR PEDAL POSITION SENSOR
CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
accelerator pedal position sensor.
3) Measure the resistance of harness between
ECM and accelerator pedal position sensor
connector.
Connector & terminal
(B135) No. 23 — (B315) No. 6:
(B135) No. 29 — (B315) No. 5:
2 CHECK HARNESS BETWEEN ECM AND AC-
CELERATOR PEDAL POSITION SENSOR
CONNECTOR.
1) Connect the connector to ECM.
2) Measure the resistance between accelera-
tor pedal position sensor connector and chassis
ground.
Connector & terminal
(B315) No. 5 — Chassis ground:
3 CHECK HARNESS BETWEEN ECM AND AC-
CELERATOR PEDAL POSITION SENSOR
CONNECTOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between accelerator
pedal position sensor connector and chassis
ground.
Connector & terminal
(B315) No. 6 (+) — Chassis ground (–):
4 CHECK HARNESS BETWEEN ECM AND AC-
CELERATOR PEDAL POSITION SENSOR
CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance between ECM con-
nectors.
Connector & terminal
(B135) No. 21 — (B135) No. 23:
Check
Is the resistance less than 1 ? Go to step 2.
Is the resistance less than 5 ? Go to step 3.
Is the voltage 4.85 V or more? Repair the short
Is the resistance 1 M or
more?
EN(H4DOTC)(diag)-331
ENGINE (DIAGNOSTICS)
Yes No
Repair the open
circuit in harness
between ECM and
accelerator pedal
position sensor
connector.
Repair the harness
and connector.
NOTE:
In this case, repair
the following item:
• Open circuit of
harness between
ECM and engine
ground
• Poor contact of
ECM connector
• Poor contact of
coupling connector
Go to step 4.
circuit to power
supply in the har-
ness between the
ECM and accelera-
tor pedal position
sensor connector.
Repair the poor Repair the short
contact of acceler- circuit to power
ator pedal position supply in the har-
sensor connector. ness between the
Replace the accel- ECM and accelera-
erator pedal if tor pedal position
defective. <Ref. to sensor connector.
SP(H4SO)-4,
Accelerator
Pedal.>