Subaru 2009 IMPREZA Service Manual page 667

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK FRONT OXYGEN (A/F) SENSOR
CONNECTOR AND COUPLING CONNEC-
TOR.
2 CHECK HARNESS BETWEEN ECM AND
FRONT OXYGEN (A/F) SENSOR CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance between ECM and
chassis ground.
Connector & terminal
(B135) No. 9 — Chassis ground:
(B135) No. 8 — Chassis ground:
3 CHECK OUTPUT SIGNAL FOR ECM.
1) Connect the connector to ECM.
2) Turn the ignition switch to ON.
3) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B135) No. 9 (+) — Chassis ground (–):
4 CHECK OUTPUT SIGNAL FOR ECM.
Measure the voltage between ECM and chassis
ground.
Connector & terminal
(B135) No. 8 (+) — Chassis ground (–):
5 CHECK OUTPUT SIGNAL FOR ECM.
Measure the voltage between ECM and chassis
ground.
Connector & terminal
(B135) No. 9 (+) — Chassis ground (–):
(B135) No. 8 (+) — Chassis ground (–):
CJ:DTC P1160 RETURN SPRING FAILURE
NOTE:
For the diagnostic procedure, refer to DTC P2101. <Ref. to EN(H4SO)(diag)-282, DTC P2101 THROTTLE
ACTUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
Check
Has water entered the connec-
tor?
Is the resistance 1 M or
more?
Is the voltage 4.5 V or more?
Is the voltage 4.95 V or more? Go to step 5.
Is the voltage 8 V or more?
EN(H4SO)(diag)-250
Yes No
Completely Go to step 2.
remove any water
inside.
Go to step 3. Repair the ground
short circuit of har-
ness between
ECM and front oxy-
gen (A/F) sensor
connector.
Go to step 5. Go to step 4.
Replace the front
oxygen (A/F) sen-
sor. <Ref. to
FU(H4SO)-41,
Front Oxygen (A/F)
Sensor.>
Repair the short Repair the poor
circuit to power in contact of ECM
the harness connector.
between ECM and
front oxygen (A/F)
sensor connector.
After repair,
replace the ECM.
<Ref. to
FU(H4SO)-45,
Engine Control
Module (ECM).>