Entering Diagnostic Mode

Prior to entering diagnostic mode, the following conditions must be met: Engine must be at normal operating temperature, battery voltage above 11 volts, transmission in Neutral, throttle valve fully closed and A/C off.
Turn ignition on, but DO NOT start engine. Remove rubber cap from "CHECK ENGINE" connector. See Fig 2. Using a jumper wire, jumper both terminals of the connector together.

Fig 1: Example of Trouble Code Output

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NOTE: Output is in the form of voltmeter needle fluctuations.

Fig 2: Jumping "CHECK ENGINE" Connector

NOTE: Insert the jumper wire into the "CHECK ENGINE" connector.