1990 Mercedes Benz 350SDFACTORY OEM SERVICE PROCEDURE

Testing Preparation

To test EDS system after malfunction codes are retrieved, use Multi-meter and Socket Box Tester (124 589 00 21 00) connected by test cables to EDS control unit. See Figure . Connect multimeter leads to socket box tester pin sockets No. 11 and 3. Remove EDS control unit connector. Connect socket box tester connectors to EDS control unit and EDS control unit harness connector according to the diagram. See Figure .

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.