Entering Or Exiting Diagnostic Mode (Non-Scan)

1988 Chevrolet Cavalier VL, StandardSECTION Entering Or Exiting Diagnostic Mode (Non-Scan)
  1. Turn ignition on. Do not start engine. "SERVICE ENGINE SOON" light should glow. Locate Assembly Line Data Link (ALDL) connector attached to ECM wiring harness under instrument panel, left or right of steering column (under cigar lighter plate in center console on Fiero). Insert jumper wire across terminal "B", "DIAGNOSTIC TERMINAL" and terminal "A", "GROUND". See Fig 1 .
    CAUTION: Inserting spade lug (jumper lead) into terminals of ALDL connector grounds "DIAGNOSTIC TERMINAL". Do not ground ALDL connector until after ignition is on (engine not running).
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.