Subaru Legacy 2002 Service Manual page 613

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
7 CHECK POWER SUPPLY TO REAR OXY-
GEN SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from rear oxygen
sensor.
3) Turn ignition switch to ON.
4) Measure voltage between rear oxygen sen-
sor connector and engine ground or chassis
ground.
Connector & terminal
(T6) No. 2 (+) — Chassis ground (−):
8 CHECK REAR OXYGEN SENSOR.
1) Turn ignition switch to OFF.
2) Measure resistance between rear oxygen
sensor connector terminals.
Terminals
No. 1 — No. 2:
Step
Is the voltage more than 10
V?
Is the resistance less than
30 Ω?
EN-96
Check Yes
Go to step 8.
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
rear oxygen sen-
sor and ECM con-
nector
¼ Poor contact in
rear oxygen sen-
sor connector
¼ Poor contact in
ECM connector
¼ Poor contact in
coupling connec-
tor (T5)
No
Repair power sup-
ply line.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
main relay and
rear oxygen sen-
sor connector
¼ Poor contact in
rear oxygen sen-
sor connector
¼ Poor contact in
coupling connec-
tor (T5)
Replace rear oxy-
gen sensor. <Ref.
to FU-49, Rear
Oxygen Sensor.>