Ford EEC Self-Test Connector Hookup Diagram - Read Codes with Test Light

This document is a line-art diagram titled "TEST HOOKUPS" showing how to connect test equipment to a vehicle's self-test connectors to read diagnostic trouble codes. It identifies the self-test connectors (a larger multi-pin connector and a smaller single-terminal connector) and labels the key terminals: Signal Return (SIG RTN), Self Test Input (STI, also called the trigger), and Self Test Output (STO). The instructions state that codes can be read on a test light or an analog voltmeter connected from the Self Test Output to battery positive. To start the self-test, the reader is told to jump the Self Test Input to Signal Return. Two hookup arrangements are illustrated: on the left, a test light connected from the STO terminal to the battery positive terminal with a jumper between STI and SIG RTN; on the right, the same jumper arrangement with an analog voltmeter connected from the connector to the battery positive terminal. A reader learns which connector pins to use, how to trigger the self-test, and two acceptable methods (test light or analog voltmeter) for reading the flashed codes. The document itself contains no year, model, or part number information.