Subaru Legacy 2002 Service Manual page 806

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
No.
1 CHECK INPUT SIGNAL FOR ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chas-
sis ground.
Connector & terminal
(B135) No. 16 (+) — Chassis ground
(−):
2 CHECK INPUT SIGNAL FOR ECM.
Measure voltage between ECM and chassis
ground.
Connector & terminal
(B135) No. 16 (+) — Chassis ground
(−):
3 CHECK POOR CONTACT.
Check poor contact in ECM connector.
4 CHECK HARNESS BETWEEN ECM AND
TCM CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from ECM and
TCM.
3) Measure resistance of harness between
ECM and TCM connector.
Connector & terminal
(B135) No. 16 — (B56) No. 5:
5 CHECK HARNESS BETWEEN ECM AND
TCM CONNECTOR.
Measure resistance of harness between ECM
and chassis ground.
Connector & terminal
(B135) No. 16 — Chassis ground:
6 CHECK POOR CONTACT.
Check poor contact in TCM connector.
Step
Is the voltage more than
4.5 V?
Is the voltage more than 10
V?
Is there poor contact in
ECM connector?
Is the resistance less than
1 Ω?
Is the resistance less than
10 Ω?
Is there poor contact in
TCM connector?
EN-289
Check Yes
Go to step 2.
Repair battery
short circuit in
harness between
ECM and TCM
connector.
Repair poor con-
tact in ECM con-
nector.
Go to step 5.
Repair ground
short circuit in
harness between
ECM and TCM
connector.
Repair poor con-
tact in TCM con-
nector.
Engine (Diagnostics)
No
Go to step 4.
Go to step 3.
Replace ECM.
<Ref. to FU-51,
Engine Control
Module.>
Repair open cir-
cuit in harness
between ECM
and TCM connec-
tor.
Go to step 6.
Replace TCM.
<Ref. to AT-49,
Transmission
Control Module
(TCM).>