Subaru Forester 2004 Service Manual page 229

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTIC)
Step
14 CHECK SENSOR OUTPUT.
1) Read the data of sub throttle sensor signal
using Subaru Select Monitor.
2) Check the voltage change by shaking the
harness and connector of ECM, engine har-
ness connector and electronic throttle control
connector.
15 CHECK POOR CONTACT.
Check the poor contact in connector between
ECM and electronic throttle control.
16 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Disconnect the connectors from the elec-
tronic throttle control.
4) Measure the resistance between ECM con-
nector and electronic throttle control connector.
Connector & terminal
(B136) No. 18 — (E57) No. 6:
(B136) No. 29 — (E57) No. 4:
(B136) No. 35 — (E57) No. 3:
17 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
1) Connect the ECM connector.
2) Measure the resistance between electronic
throttle control connector and engine ground.
Connector & terminal
(E57) No. 3 — Engine ground:
18 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. 5 (+) — Engine ground (
3) Check the voltage change by shaking the
harness and connector of ECM and engine
harness connector while monitoring the value
with voltage meter.
19 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
1) Measure the voltage between electronic
throttle control connector and engine ground.
Connector & terminal
(E57) No. 4 (+) — Engine ground (
(E57) No. 6 (+) — Engine ground (
2) Check the voltage change by shaking the
harness and connector of ECM and engine
harness connector while monitoring the value
with voltage meter.
Check
Is the voltage 4.73 V?
Is there poor contact?
Is the resistance less than 1
Ω?
Is the resistance less than 5
Ω?
Is the voltage more than 10 V? Go to step 19.
−
):
Is the voltage less than 10 V?
−
):
−
):
EN(H4DOTC 2.5)-228
Yes
Go to step 15. Go to step 16.
Repair the poor Go to step 21.
contact.
Go to step 17. Repair the open
circuit of harness
connector.
Go to step 18. Repair the poor
contact in ECM
connector.
Replace the ECM
if defective.
Repair battery
short circuit in har-
ness between ECM
connector and elec-
tronic throttle con-
trol connector.
Go to step 20. Repair short circuit
in harness
between ECM
connector and
electronic throttle
control connector.
No