Test Switch Terminal

RH Rear Of Engine Compartment:

TEST SWITCH TERMINAL

DESCRIPTION
The test switch terminal is included in the Duty Check Data Link Connector (DLC). When this terminal is grounded, the Engine Control Module (ECM) sets the ignition timing to base timing.

When both the test switch terminal and the diagnostic request switch terminal are grounded simultaneously, the ECM displays any Diagnostic Trouble Codes (DTCs) to the Malfunction Indicator Lamp (MIL) and outputs air/fuel duty through the duty check terminal in the Duty Check DLC.