Diagnostic Testing

1993 Cadillac DeVille Base, 4D SedanSECTION Diagnostic Testing
NOTE: Diagnostic testing using diagnostic system is intended for use with TROUBLE CODE CHART. See Figure and Figure. Before using trouble code chart, become completely familiar with procedures in SELF-DIAGNOSTICS.

To make diagnostic tests available, system must first be programmed to display .7.0 on FDC. See ENTERING SELF-DIAGNOSTICS  and DISPLAYING TROUBLE CODES . With .7.0 displayed, technician may select desired diagnostic test. The following choices are available:

  • PCM Switch Tests:  Not applicable to charging system.
  • PCM Data Parameters:  To select, see PCM DATA DISPLAY .
  • PCM Code Snapshot:  To select, see SNAPSHOT .
  • PCM Instant Snapshot:  To select, see SNAPSHOT .
  • PCM Output Cycling:  Not applicable to charging system.
  • PCM Output Overrides:  Not applicable to charging system.
  • BCM Data Display:  Not applicable to charging system.
  • ECC Program Override:  Not applicable to charging system.
  • Clear Codes:  See CLEARING TROUBLE CODES .
  • Exit Diagnostics:  See EXITING SELF-DIAGNOSTICS .
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:

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