Subaru Legacy 2005 Service Manual page 1425

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK ELECTRONIC THROTTLE CON-
TROL RELAY.
1) Turn the ignition switch to OFF.
2) Remove the electronic throttle control relay.
3) Connect the battery to electronic throttle
control relay terminals No. 5 and No. 6.
4) Measure the resistance between electronic
throttle control relay terminals.
Terminals
No. 7 — No. 8:
2 CHECK POWER SUPPLY OF ELECTRONIC
THROTTLE CONTROL RELAY.
1) Turn the ignition switch to ON.
2) Measure the voltage between electronic
throttle control relay connector and chassis
ground.
Connector & terminal
(B362) No. 8 (+) — Chassis ground (
(B362) No. 5 (+) — Chassis ground (
3 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL RE-
LAY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Turn the ignition switch to ON.
4) Measure the voltage between electronic
throttle control relay connector and chassis
ground.
Connector & terminal
(B362) No. 6 (+) — Chassis ground (
4 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL RE-
LAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between electronic
throttle control relay connector and chassis
ground.
Connector & terminal
(B362) No. 6 — Chassis ground:
(B362) No. 7 — Chassis ground:
5 CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL RE-
LAY.
Measure the resistance between ECM connec-
tor and electronic throttle control relay connec-
tor.
Connector & terminal
(B135) No. 35 — (B362) No. 6:
(B137) No. 6 — (B362) No. 7:
6 CHECK SENSOR OUTPUT.
1) Connect all the connectors.
2) Turn the ignition switch to ON.
3) Measure the voltage between ECM con-
nector terminals.
Connector & terminal
(B136) No. 18 (+) — (B136) No. 35 (
Check
Is the resistance less than 1
Ω?
Is the voltage more than 10 V? Go to step 3.
−
):
−
):
Is the voltage more than 10 V? Repair the power
−
):
Is the resistance more than 1
MΩ?
Is the resistance less than 1
Ω?
Is the voltage more than 0.4 V? Go to step 7.
−
):
EN(H4DOTC)(diag)-185
ENGINE (DIAGNOSTICS)
Yes
Go to step 2. Replace the elec-
tronic throttle con-
trol relay.
Repair the open or
ground short cir-
cuit of power sup-
ply circuit.
Go to step 4.
supply short cir-
cuit of harness
between ECM and
electronic throttle
control.
Go to step 5. Repair the ground
short circuit of har-
ness between
ECM and elec-
tronic throttle con-
trol relay.
Go to step 6. Repair the open
circuit of harness
between ECM and
electronic throttle
control relay.
Go to step 9.
No