Retrieving Codes (Non-Scan)

1994 Chevrolet Suburban K2500, 5.7 KSECTION Retrieving Codes (Non-Scan)
NOTE: The Assembly Line Data Link (ALDL) connector may also be referred to as the Data Link Connector (DLC) in flow charts. This is the same connector.
  1. Turn ignition on with engine off. Malfunction Indicator Light (MIL) should glow. Locate Data Link Connector (DLC), attached to ECM wiring harness. Most DLCs are located under dash on driver's side of vehicle. For exact location of DLC, see appropriate COMPONENT LOCATIONS illustration in appropriate I - SYS/COMP TESTS article in the ENGINE PERFORMANCE section below. Turn ignition on. Insert jumper wire from terminal "B" (diagnostic test terminal) to terminal "A" (ground) of DLC. See Fig 1.
  2. Malfunction Indicator Light (MIL) should flash codes. Each code is flashed 3 times. If codes DO NOT flash, perform DIAGNOSTIC CIRCUIT CHECK in appropriate BASIC TESTING article in the ENGINE PERFORMANCE section above. To exit diagnostic mode, turn ignition off and remove jumper wire from DLC.
Fig 1: ALDL/DLC Diagnostic Connector Terminal ID
G90B01199Courtesy of GENERAL MOTORS CORP.
RENDER: 1.0x

NO RELATED

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

  • β€’ You smell fuel, burning insulation, or see smoke.
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