Actron 9640A GM On-Board Diagnostics, Ford On-Board Diagnostics, Chrysler On-Board Diagnostics

Getting Started

The original on-board diagnostics (OBD I) lacked consistency in communica- tion and interface while allowing different interpretations amongst vehicle man- ufacturers. Ford and Chrysler used different types of engine control computers and data link connectors, and GM varied the trouble codes and communication protocols from year-to-year.

The tables below highlight changes for GM, Ford, and Chrysler. If this seems confusing; don’t worry. Your tool makes it easy. Based on the VIN information selected during Scan Tool setup, the processor is automatically recognized. All you have to do is choose the correct adapter cable and jumper wires (if nec- essary). Details on adapter cables and jumper wires may be found in “Diag- nostic Link Connectors (DLC)” on page 2-3.

GM On-Board Diagnostics

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	System	Years	Description
			Most vehicles used the 12-pin ALDL (Assembly Line Data Link)
	OBD I Control Module		located under the dash on the driver side. Some 94-95 vehicles
		1981–1995	used the 16-pin OBD II (J1962) data link connector (DLC), but
			use the Historical application software. Refer to the vehicle’s
			Vehicle Emission Control Information label.
	OBD II Control Module	1994*-Present	Complies with OBD II regulations and uses the J1962 DLC.

*OBD II system used in certain 1994-1995 vehicles equipped with a 2.2L, 2.3L, 3.8L, 4.3L or 5.7L engines.

Ford On-Board Diagnostics

System	Long Name	Years		Description
MCU	Microprocessor Control Unit	1980	–1991	Used in police vehicles, containing carbureted
				engines. Uses the MCU DLC.
EEC-IV	Electronic Engine Control,	1984	–1995	Most Ford vehicles equipped with North American
	Fourth generation			engines. Uses the EEC-IV DLC.
MECS	Mazda Electronic Control	1988	–1995	Vehicles equipped with Mazda-sourced engines.
	System			Uses MECS 6-pin and 17-pin DLCs.
EEC-V	Electronic Engine Control,	1994* – present		Complies with OBD II regulations and uses the
	Fifth generation			OBD II J1962 DLC.
PTEC	Powertrain Electronic Con-	2000	– present	Complies with OBD II regulations and uses the
	troller			OBD II J1962 DLC.

*EEC-V OBD II system used in 1994-1995 vehicles equipped with a 3.8L or 4.6L engine.

Chrysler On-Board Diagnostics

System	Long Name	Years	Description
SMEC	Single Module Engine	1989–1990	Used a 6-pin Serial Communication Interface (SCI) DLC
	Controller		and has bidirectional capability.
SBEC	Single Board Engine		Used two types of DLCs: a 6-pin SCI and a 6-pin LH
		1989*–1995	series.
	Controller
			The first to allow a tool to reset the EMR light on trucks.
OBD II	OBD II Powertrain	1995**– present	Complies with OBD II regulations and uses the OBD II
PCM	Control Module		J1962 DLC.
JTEC	Jeep/Truck Engine		Complies with OBD II regulations and uses the OBD II
		1996– present	J1962 DLC.
	Controller
			The JTEC system is used on light-duty trucks and Jeeps

*In 1989, the SBEC system was installed in selected vehicles with 3.0L V6 engines.

**Some vehicles in 1995 were equipped with the OBD II PCM.

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