Subaru Legacy 2004 Service Manual page 889

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK OPTION CODE.
2 CHECK ANY OTHER DTC ON DISPLAY.
3 CHECK REAR OXYGEN SENSOR DATA.
1) Warm-up the engine until engine coolant
temperature is above 70#C (158#F), and keep
the engine speed at 5,000 rpm.
2) Read the data of rear oxygen sensor signal
using Subaru Select Monitor.
NOTE:
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE". <Ref.
to EN(H4SO 2.5)(diag)-26, Subaru Select Mon-
itor.>
4 CHECK HARNESS BETWEEN ECM AND
REAR OXYGEN SENSOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and
rear oxygen sensor.
3) Measure the resistance in harness
between ECM and rear oxygen sensor con-
nector.
Connector & terminal
(B137) No. 24 — (B19) No. 3:
(B136) No. 35 — (B19) No. 4:
Check
Is the option code EC, EK or
K4?
Is any other DTC displayed?
Is the voltage more than 490
mV?
Is the resistance more than 3
!?
EN(H4SO 2.5)(diag)-130
Yes
Go to step 2. Refer to EN(H4SO
2.0) section. <Ref.
to EN(H4SO
2.0)(diag)-66, List
of Diagnostic Trou-
ble Code (DTC).>
NOTE:
Fuel injection sys-
tem for KA and KS
model is the same
as 2.0 L model.
Inspect the DTC Go to step 3.
using "List of Diag-
nostic Trouble
Code (DTC)".
<Ref. to EN(H4SO
2.5)(diag)-70, List
of Diagnostic Trou-
ble Code (DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0137.
Go to step 6. Go to step 4.
Repair the open Go to step 5.
circuit in harness
between ECM and
rear oxygen sen-
sor connector.
No