Subaru 2009 IMPREZA Service Manual page 691

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
27 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
1) Connect the connector to ECM.
2) Measure the resistance between electronic
throttle control connector and engine ground.
Connector & terminal
(E57) No. 3 — Engine ground:
28 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
1) Turn the ignition switch to ON.
2) Measure the voltage between electronic
throttle control connector and engine ground.
Connector & terminal
(E57) No. 6 (+) — Engine ground (–):
(E57) No. 4 (+) — Engine ground (–):
29 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance between ECM con-
nectors.
Connector & terminal
(B134) No. 19 — (B134) No. 18:
(B134) No. 19 — (B134) No. 28:
30 CHECK SENSOR OUTPUT.
1) Connect all connectors.
2) Turn the ignition switch to ON.
3) Read the data of main throttle sensor signal
using Subaru Select Monitor.
NOTE:
For detailed operation procedures, refer to
"READ CURRENT DATA FOR ENGINE". <Ref.
to EN(H4SO)(diag)-34, Subaru Select Moni-
tor.>
31 CHECK SENSOR OUTPUT.
Read the data of sub throttle sensor signal
using Subaru Select Monitor.
NOTE:
Subaru Select Monitor
For detailed operation procedures, refer to
"READ CURRENT DATA FOR ENGINE". <Ref.
to EN(H4SO)(diag)-34, Subaru Select Monitor.>
32 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL MO-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
electronic throttle control.
3) Measure the resistance between ECM and
electronic throttle control connector.
Connector & terminal
(B137) No. 5 — (E57) No. 2:
(B137) No. 4 — (E57) No. 1:
Check
Is the resistance less than 5 ? Go to step 28.
Is the voltage 4.85 V or more? Repair the short
Is the resistance 1 M or
more?
Is the voltage 0.81 — 0.87 V?
Is the voltage 1.64 — 1.70 V?
Is the resistance less than 1 ? Go to step 33.
EN(H4SO)(diag)-274
Yes 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
ECM connector
• Poor contact of
coupling connector
Go to step 29.
circuit to power in
harness between
ECM and elec-
tronic throttle con-
trol connector.
Go to step 30. Repair the short
circuit to power in
harness between
ECM and elec-
tronic throttle con-
trol connector.
Go to step 31. Repair the poor
contact of elec-
tronic throttle con-
trol connector.
Replace the elec-
tronic throttle con-
trol if defective.
<Ref. to
FU(H4SO)-14,
Throttle Body.>
Go to step 32. Repair the poor
contact of electronic
throttle control con-
nector. Replace the
electronic throttle
control if defective.
<Ref. to FU(H4SO)-
14, Throttle Body.>
Repair the harness
and connector.
NOTE:
In this case, repair
the following item:
• Open circuit in
harness between
ECM and electron-
ic throttle control
connector
• Poor contact of
coupling connector