Actron 9640 Manuel D’Utilisation

The original on-board diagnostics (OBD I) lacked consistency in 

communication and interface while allowing different interpretations amongst 

vehicle manufacturers. 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 

necessary). Details on adapter cables and jumper wires may be found in 

“Diagnostic Link Connectors (DLC)” on page 2-5
.

1981–1995

Most vehicles used the 12-pin ALDL (Assembly Line Data Link) 

located under the dash on the driver side. Some 94-95 vehicles 

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.

1994*-Present Complies with OBD II regulations and uses the J1962 DLC.

Microprocessor Control Unit 1980 –1991

Used in police vehicles, containing carbureted 

engines. Uses the MCU DLC.

EEC-IV Electronic Engine Control, 

Fourth generation

1984 –1995

Most Ford vehicles equipped with North 

American engines. Uses the EEC-IV DLC.

MECS Mazda Electronic Control 

System

1988 –1995

Vehicles equipped with Mazda-sourced engines. 

Uses MECS 6-pin and 17-pin DLCs.

EEC-V Electronic Engine Control, 

Fifth generation

1994* – present Complies with OBD II regulations and uses the 

OBD II J1962 DLC. 

Powertrain Electronic 

Controller

2000 – present Complies with OBD II regulations and uses the 

OBD II J1962 DLC.