Inspection Procedure

WIRING DIAGRAM





PROCEDURE
1. Check voltage between terminal ISCO, ISCC of engine control module connector and body ground.
- Turn up the floor mat on the passenger side.
- Disconnect the engine control module (ECM) connectors.
- Turn ignition switch ON.




- Measure voltage between terminals ISCO, ISCC of engine control module connector and body ground.
Voltage spec.- 9 - 14 volts
^ If OK Check and replace engine control module.
^ If not OK proceed to step 2.
2. Check operation of the IAC valve.
- Disconnect IAC valve connector.
- Remove IAC valve.




(1) Connect the positive (+) lead from the battery to terminal 2 (+B) and negative (-) lead to terminal 3 (ISCC) and check that the valve is closed.
OK if: The valve is closed.




(2) Connect the positive (+) lead from the battery to terminal 2 (+B) and negative (-) lead to terminal 1 (ISCO) and check that the valve is open.
OK if: The valve is open.
^ If OK proceed to step 3.
^ If not OK Replace IAC valve.
3. Check for open and short in harness and connector between R/B No.2 and IAC valve, IAC valve and engine control module.
^ If OK check for ECM power source circuit.
ECM Power Source Circuit
^ If not OK repair or replace harness or connector.