1993 Mercedes Benz 400EFACTORY OEM SERVICE PROCEDURE

Retrieving Codes: LH-SFI: Notes

NOTE: Before using Diagnostic Trouble Codes (DTCs) to diagnose vehicle, LH-SFI control unit must first be allowed to display on/off ratio through On/Off Ratio Tester (909 589 00 21 00).
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Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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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.