Actron 9640 Manuel D’Utilisation

In the KOEO Procedure, Field Service can check relays, solenoids and the idle 

speed motor, and obtain DTCs using the CHECK ENGINE light. 

1) Turn ignition Key ON but DO NOT Start Engine.
2) On scan tool, place Field Service On.
3) The Check Engine light will begin to flash codes. Each DTC is displayed 

three (3) times. The DTCs are displayed starting with the lowest numbered 

one. After all DTCs are displayed, the sequence keeps repeating until the 

ignition key or Field Service mode is turned OFF.

—   Count CHECK ENGINE Light Flashes to obtain trouble codes. The first 

digit is sent first. A short pause separates digits while a long pause 

separates each DTC. All codes contain 2 digits. 

—   DTC 12 (No RPM reference pulse) should display first since the engine 

is not running. If not, problems exist in the PCM or Check Engine light 

circuitry.

FLASH-pause-FLASH-FLASH — long pause.

FLASH-FLASH-pause-FLASH-FLASH-FLASH — long pause.

4) When Field Service Mode is ON, most computer controlled Relays and 

Solenoids will be turned ON, except for the fuel pump relay and fuel 

injectors. Toggle the Field Service Mode On and Off.

❒

Use a voltmeter to measure Relays and Solenoids input voltage to 

verify On/Off conditions. An ohmmeter could be used to check the 

continuity between the relay’s switch terminals.

❒

The Idle Air Control (IAC) valve is fully seated to the zero position by 

the PCM. 

❒

The Exhaust Gas Recirculation (EGR) solenoid is energized for 25 

seconds.