1982 Mercedes Benz 380SLFACTORY OEM SERVICE PROCEDURE

Electronic Control Unit

The control unit receives voltage from the voltage supply relay (No. 29). It also has inputs from ignition system (to determine idle speed), a coolant sensor, air injection system and fuel injection feedback control unit. It provides an output signal to idle speed adjuster which varies from 1 to 5 volts, at a frequency of 200 cycles per second.

NOTE: The electronic control unit is located in a sealed box in front of cowl air intake grille.
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.