Subaru Legacy 2003 Service Manual page 680

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
1 CHECK ANY OTHER DTC ON DISPLAY.
Is there any DTC on display?
2 CHECK ECM GROUND CIRCUIT.
1) Turn ignition switch to OFF.
2) Measure resistance between ECM connec-
tor and chassis ground.
Connector & terminal
(B134) No. 7 - Chassis ground:
(B137) No. 14 - Chassis ground:
(B135) No. 21 - Chassis ground:
Is the measured value less than the speci-
fied value?
3 CHECK HARNESS BETWEEN ECM AND
EGR SOLENOID VALVE CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from EGR solenoid
valve.
3) Turn ignition switch to ON.
4) Measure voltage between ECM connector
and chassis ground.
Connector & terminal
DTC P1493; (B134) No. 18 - Chassis
ground:
DTC P1495; (B134) No. 17 - Chassis
ground:
DTC P1497; (B134) No. 16 - Chassis
ground:
DTC P1499; (B134) No. 15 - Chassis
ground:
Does the measured value exceed the spec-
ified value?
Value
Other DTC indicated on dis-
play.
5 Ω
10 V
EN(H4SO)-283
ENGINE (DIAGNOSTICS)
Yes
Go to step 2. Go to step 3.
Go to step 3. Repair harness
and connector.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM connector
and engine ground
• Poor contact in
ECM connector
• Poor contact in
coupling connector
Repair ground Replace ECM.
short circuit <Ref. to
between ECM and FU(H4SO)-45,
EGR solenoid Engine Control
valve connector. Module.>
After completion of
repair, replace
ECM. <Ref. to
FU(H4SO)-45,
Engine Control
Module.>
No