Duty Check Data Link Connector

RH Rear Of Engine Compartment:

DIAGNOSTIC REQUEST TERMINAL

DESCRIPTION
The Diagnostic Request Terminal, located in the Duty Check Data Link Connector (DLC), provides for communications with the Engine Control Module (ECM). The Duty Check DLC is located in the RH rear engine compartment near the battery (Refer to accompanying image).

OPERATION
When cavity "2," the Diagnostic Request Terminal, is grounded through cavity "3," a signal is fed to the Engine Control Module (ECM) which then outputs a Diagnostic Trouble Code (DTC) to the Malfunction Indicator Lamp (MIL), and at the same time outputs the idle air control duty cycle through the Duty Check Terminal in the Duty Check DLC.