Subaru Legacy 2002 Service Manual page 1418

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
No.
1 CHECK HARNESS BETWEEN KNOCK
SENSOR 2 (LH) AND ECM CONNECTOR.
Measure resistance of harness between ECM
connector and chassis ground.
Connector & terminal
(B135) No. 13 — Chassis ground:
2 CHECK KNOCK SENSOR 2 (LH).
1) Disconnect connector from knock sensor 2
(LH).
2) Measure resistance between knock sensor
2 (LH) connector terminal and engine ground.
Terminal
No. 2 — Engine ground:
3 CHECK INPUT SIGNAL FOR ECM.
1) Connect connectors to ECM and knock
sensor 2 (LH).
2) Turn ignition switch to ON.
3) Measure voltage between ECM and chas-
sis ground.
Connector & terminal
(B135) No. 13 (+) — Chassis ground
(−):
Step
Is the resistance less than
400 kΩ?
Is the resistance less than
400 kΩ?
Is the voltage more than 2
V?
EN(H6)-211
Check Yes
Go to step 2.
Replace knock
sensor 2 (LH).
<Ref. to FU(H6)-
32, Knock Sen-
sor.>
Even if MIL lights
up, the circuit has
returned to a nor-
mal condition at
this time.
(However, the
possibility of poor
contact still
remains.)
NOTE:
In this case,
repair the follow-
ing:
¼ Poor contact in
knock sensor con-
nector 2 (LH)
¼ Poor contact in
ECM connector
¼ Poor contact in
coupling connec-
tor
Engine (DIAGNOSTICS)
No
Go to step 3.
Repair ground
short circuit in
harness between
knock sensor 2
(LH) connector
and ECM connec-
tor.
NOTE:
The harness
between both
connectors is
shielded. Repair
short circuit of
harness together
with shield.
Repair poor con-
tact in ECM con-
nector.