Subaru 2009 IMPREZA Service Manual page 1433

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK HARNESS BETWEEN ECM AND
SECONDARY AIR PUMP RELAY CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from the ECM
and secondary air pump relay.
3) Measure the resistance of harness between
ECM and secondary air pump relay connector.
Connector & terminal
(B136) No. 8 — (F9) No. 13:
2 CHECK HARNESS BETWEEN ECM AND
SECONDARY AIR PUMP RELAY CONNEC-
TOR.
Measure the resistance between ECM and
chassis ground.
Connector & terminal
(B136) No. 8 — Chassis ground:
Check
Is the resistance less than 1 ? Go to step 2.
Is the resistance 1 M or
more?
EN(H4DOTC)(diag)-212
Yes No
Repair the harness
and connector.
NOTE:
In this case, repair
the following item:
• Open circuit in
harness between
ECM and second-
ary air pump relay
connector
• Poor contact of
coupling connector
Even if DTC is Repair the short
detected, the cir- circuit to ground in
cuit has returned to harness between
a normal condition ECM and second-
at this time. Repro- ary air pump relay
duce the failure, connector.
and then perform
the diagnosis
again.
NOTE:
In this case, tem-
porary poor con-
tact of connector
may be the cause.