Subaru Legacy 2003 Service Manual page 621

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
1 CHECK TRANSMISSION TYPE.
Is the transmission type AT?
2 CHECK DTC P0720 ON DISPLAY.
Does the Subaru Select Monitor or OBD-II
general scan tool indicate DTC P0720?
3 CHECK SPEEDOMETER OPERATION IN
COMBINATION METER.
Does speedometer operate normally?
4 CHECK HARNESS BETWEEN ECM AND
COMBINATION METER CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from combination
meter.
3) Measure resistance between ECM and
combination meter.
Connector & terminal
(B137) No. 10 — (i10) No. 13:
Is the measured value less than the speci-
fied value?
Step
EN(H4SO)-224
Value
Transmission type is AT.
DTC P0720 indicated.
Operates normally.
10 Ω
Yes
Go to step 2. Go to step 3.
Check front vehi- Go to step 3.
cle speed sensor
signal circuit.
<Ref. to AT-58,
DTC 33 FRONT
VEHICLE SPEED
SENSOR, Diag-
nostic Procedure
with Diagnostic
Trouble Code
(DTC).>
Go to step 4. Check speedome-
ter and vehicle
speed sensor.
<Ref. to IDI-18,
Speedometer.>
and <Ref. to AT-
54, Front Vehicle
Speed Sensor.>
and <Ref. to AT-
58, Rear Vehicle
Speed Sensor.>
and <Ref. to AT-
59, Torque Con-
verter Turbine
Speed Sensor.>
Repair poor con- Repair harness
tact in ECM con- and connector.
nector.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and combi-
nation meter con-
nector
• Poor contact in
ECM connector
• Poor contact in
combination meter
connector
• Poor contact in
coupling connector
No