Subaru 2004 LEGACY Service Manual page 110

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK ANY OTHER DTC ON DISPLAY.
2 CHECK OUTPUT SIGNAL FROM ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM con-
nector and chassis ground on faulty cylinders.
Connector & terminal
#1 (B136) No. 6 (+) — Chassis ground (
#2 (B136) No. 5 (+) — Chassis ground (
#3 (B136) No. 4 (+) — Chassis ground (
#4 (B136) No. 3 (+) — Chassis ground (
#5 (B136) No. 2 (+) — Chassis ground (
#6 (B136) No. 1 (+) — Chassis ground (
3 CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from fuel injector
on faulty cylinder.
3) Measure the resistance between ECM con-
nector and engine ground on faulty cylinders.
Connector & terminal
#1 (E5) No. 1 — Engine ground:
#2 (E16) No. 1 — Engine ground:
#3 (E6) No. 1 — Engine ground:
#4 (E17) No. 1 — Engine ground:
#5 (E43) No. 1 — Engine ground:
#6 (E44) No. 1 — Engine ground:
4 CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
Measure the resistance of harness connector
between ECM connector and fuel injector on
faulty cylinders.
Connector & terminal
#1 (B136) No. 6 — (E5) No. 1:
#2 (B136) No. 5 — (E16) No. 1:
#3 (B136) No. 4 — (E6) No. 1:
#4 (B136) No. 3 — (E17) No. 1:
#5 (B136) No. 2 — (E43) No. 1:
#6 (B136) No. 1 — (E44) No. 2:
5 CHECK FUEL INJECTOR.
Measure the resistance between fuel injector
terminals on faulty cylinder.
Terminals
No. 1 — No. 2:
Check
Is any other DTC displayed?
Is the voltage more than 10 V? Go to step 7.
−
):
−
):
−
):
−
):
−
):
−
):
Is the resistance more than 1
MΩ?
Is the resistance less than 1
Ω?
Is the resistance 5 — 20 Ω?
EN(H6DO)(diag)-179
ENGINE (DIAGNOSTICS)
Yes
Inspect the DTC Go to step 2.
using "List of Diag-
nostic Trouble
Code (DTC)".
<Ref. to
EN(H6DO)(diag)-
66, List of Diag-
nostic Trouble
Code (DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0301, P0302,
P0304, P0305 and
P0306.
Go to step 3.
Go to step 4. Repair the ground
short circuit in har-
ness between fuel
injector and ECM
connector.
Go to step 5. Repair the har-
ness and connec-
tor.
NOTE:
In this case repair
the following:
• Open circuit in
harness between
ECM and fuel
injector connector
• Poor contact in
coupling connector
Go to step 6. Replace the faulty
fuel injector. <Ref.
to FU(H6DO)-26,
Fuel Injector.>
No