Circuit Description

1998 Oldsmobile Achieva 3.1 M, 4T40E/MN4SECTION Circuit Description

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. SDM measures to ensure IGNITION POSITIVE VOLTAGE is within normal range. SDM then performs DEPLOYMENT LOOP CONTINUITY test, measuring voltage difference between PASSENGER HIGH and PASSENGER LOW.

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.