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 "P" or Neutral, throttle valve fully closed and A/C off.
Turn ignition on, but DO NOT start engine. Remove rubber cap from "CHECK ENGINE" connector, near distributor. Using a jumper wire, jumper both terminals of the connector together. See Fig 1.

Fig 1: Jumpering "CHECK ENGINE" Connector Insert jumper wire in "CHECK ENGINE" connector.
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Remove rubber cap from "EFI" service connector, located near battery. Using an adapter harness (SST 09842-14010), connect adapter to service connector. Connect positive probe of an analog voltmeter to Red lead of adapter harness and negative probe to Black lead. See Fig 2.

Fig 2: Connecting Voltmeter to "EFI" Connector Make sure leads are properly connected.