Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1987 Mercedes Benz 300SDLFACTORY OEM SERVICE PROCEDURE
Trimming Plug
NOTE:
Trimming plug is installed in position "4".
- With engine off, disconnect trimming plug from socket. Steering should be in lock "2" position. Connect multimeter and set to volt scale. Probe and check voltage as shown. See Fig 1 . Voltage reading should be 5 volts.
- If voltage reading is to specification, replace trimming plug. Testing is complete. If voltage reading is not to specification, repair open circuit. If no open circuit is found, replace EDS control unit.
Factory Service Tools
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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.