ENGINE (DIAGNOSTICS)(H4DOTC) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC P1418 SECONDARY AIR INJECTION SYSTEM CONTROL “A” CIRCUIT SHORTED

DTC DETECTING CONDITION:

Immediately at fault recognition

CAUTION:

After repairing or replacing the defective part, perform the Clear Memory Mode and Inspection Mode .

WIRING DIAGRAM:

• LHD model

• RHD model

STEPCHECKYESNO

1.CHECK HARNESS BETWEEN ECM AND SECONDARY AIR PUMP RELAY.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the ECM and secondary air pump relay.

3) Measure the resistance of the harness between the ECM and secondary air pump relay terminal.

Connector & terminal

(B136) No. 8 — (F9) No. 6:

Is the resistance less than 1 Ω?

Repair open circuit of the harness between the ECM and secondary air pump relay terminal.

2.CHECK HARNESS BETWEEN ECM AND SECONDARY AIR PUMP RELAY.

Measure the voltage between ECM and chassis ground.

Connector & terminal

(B136) No. 8 (+) — Chassis ground (−):

Is the voltage 10 V or more?

Repair the short to power supply in the harness between ECM and secondary air pump relay terminal.

Temporary poor contact occurs. Check the poor contact of connector.