Subaru 2009 IMPREZA Service Manual page 1415

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
6 CHECK HARNESS BETWEEN SECONDARY
AIR PUMP RELAY AND SECONDARY AIR
PUMP CONNECTOR.
1) Turn the ignition switch to OFF.
2) Remove the secondary air pump relay.
3) Measure the resistance of harness between
secondary air pump relay connector and sec-
ondary air pump connector.
Connector & terminal
(F9) No. 11 — (F11) No. 2:
7 CHECK HARNESS BETWEEN SECONDARY
AIR PUMP CONNECTOR AND CHASSIS
GROUND.
Measure the resistance of the harness between
secondary air pump connector and chassis
ground.
Connector & terminal
(F11) No. 1 — Chassis ground:
8 CHECK SECONDARY AIR PUMP RELAY.
1) Connect the battery to terminals No. 12 and
No. 13 of the secondary air pump relay.
2) Measure the resistance between secondary
air pump relay terminals.
Terminals
No. 14 — No. 11:
9 CHECK SECONDARY AIR PUMP RELAY
POWER SUPPLY.
1) Turn the ignition switch to ON.
2) Measure the voltage between the second-
ary air pump relay connector and chassis
ground.
Connector & terminal
(F9) No. 14 (+) — Chassis ground (–):
(F9) No. 12 (+) — Chassis ground (–):
10 CHECK HARNESS BETWEEN ECM AND
SECONDARY AIR PUMP RELAY CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector of ECM.
3) Measure the resistance of harness between
ECM and secondary air pump relay connector.
Connector & terminal
(B136) No. 8 — (F9) No. 13:
Check
Is the resistance less than 1 ? Go to step 7.
Is the resistance less than 5 ? Go to step 8.
Is the resistance less than 1 ? Go to step 9.
Is the voltage 10 V or more?
Is the resistance less than 1 ? Repair the poor
EN(H4DOTC)(diag)-194
Yes No
Repair the open
circuit in harness
between second-
ary air pump relay
connector and sec-
ondary air pump
connector.
Repair the open
circuit of the har-
ness between sec-
ondary air pump
connector and
chassis ground.
Replace the sec-
ondary air pump
relay. <Ref. to
EN(H4DOTC)(diag)
-8, Electrical Com-
ponent Location.>
Go to step 10. Repair the open or
ground short circuit
of power supply
circuit.
Repair the harness
contact of ECM and connector.
connector.
NOTE:
In this case, repair
the following item:
• Repair the open
circuit in harness
between ECM con-
nector and sec-
ondary air pump
relay connector.
• Poor contact of
coupling connector