Subaru 2009 IMPREZA Service Manual page 703

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
18 CHECK ELECTRONIC THROTTLE CON-
TROL GROUND CIRCUIT.
Measure the resistance between ECM and
chassis ground.
Connector & terminal
(B134) No. 5 — Chassis ground:
(B137) No. 1 — Chassis ground:
(B137) No. 2 — Chassis ground:
(B137) No. 3 — Chassis ground:
(B137) No. 7 — Chassis ground:
19 CHECK ELECTRONIC THROTTLE CON-
TROL.
Measure the resistance between electronic
throttle control terminals.
Terminals
No. 2 — No. 1:
20 CHECK ELECTRONIC THROTTLE CON-
TROL.
Move the throttle valve to the fully open and fully
closed positions with fingers.
Check that the valve returns to the specified
position when releasing fingers.
Check
Is the resistance less than 5 ? Go to step 19.
Is the resistance 50
Does the valve return to the
specified position?Standard
value: 3 mm (0.12 in) from fully
closed position
EN(H4SO)(diag)-286
Yes
or less? Go to step 20.
Repair the poor
contact of ECM
connector.
No
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
coupling connector
Replace the elec-
tronic throttle con-
trol. <Ref. to
FU(H4SO)-14,
Throttle Body.>
Replace the elec-
tronic throttle con-
trol. <Ref. to
FU(H4SO)-14,
Throttle Body.>