Subaru Legacy 2003 Service Manual page 608

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
1 CHECK SPEEDOMETER AND TACHOME-
TER OPERATION IN COMBINATION
METER.
Does speedometer and tachometer operate
normally?
2 CHECK INPUT SIGNAL FOR ECM.
1) Turn ignition switch to ON. (Engine OFF)
2) Measure voltage between ECM connector
and chassis ground.
Connector & terminal
(B136) No. 27 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
3 CHECK INPUT VOLTAGE OF ECM.
1) Turn ignition switch to OFF.
2) Disconnect combination meter connector
(i10) and ECM connector.
3) Turn ignition switch to ON.
4) Measure voltage of harness between ECM
and chassis ground.
Connector & terminal
(B136) No. 27 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
4 CHECK HARNESS BETWEEN ECM AND
FUEL TANK CORD.
1) Turn ignition switch to OFF.
2) Separate fuel tank cord connector (R57)
and rear wiring harness connector (R15).
3) Measure resistance between ECM and fuel
tank cord.
Connector & terminal
(B136) No. 27 — (R15) No. 2:
Is the measured value less than the speci-
fied value?
5 CHECK HARNESS BETWEEN FUEL TANK
CORD AND CHASSIS GROUND.
Measure resistance between fuel tank cord
and chassis ground.
Connector & terminal
(R15) No. 6 — Chassis ground:
Is the measured value less than the specified
value?
Value
Operates normally.
4.75 V
4.75 V
5 Ω
5 Ω
EN(H4SO)-211
ENGINE (DIAGNOSTICS)
Yes
Go to step 2. Repair or replace
combination
meter. <Ref. to
IDI-4, Combina-
tion Meter Sys-
tem.>
Go to step 3. Even if MI lights
up, the circuit has
returned to a nor-
mal condition at
this time. A tempo-
rary poor contact
of the connector
may be the cause.
NOTE:
In this case, repair
the following:
• Poor contact in
fuel pump connec-
tor
• Poor contact in
coupling connector
Repair battery Go to step 4.
short circuit
between ECM and
combination meter
connector.
Go to step 5. Repair open circuit
between ECM and
fuel tank cord.
Go to step 6. Repair open circuit
between fuel tank
cord and chassis
ground.
NOTE:
In this case, repair
the following:
Poor contact in
coupling connec-
tors
No