How to Replace the Neutral Safety Switch in a 300D Mercedes

1. Lift the hood and prop it open. Loosen the negative cable from the battery and remove it.
2. Jack up your 300D under the rear frame and lower the car onto the jack stands.
3. Locate the neutral safety switch, which is mounted directly above the transmission pan.
4. Unplug the plastic wiring harness attached to the back of the switch. Use a wrench to remove the hex nut that holds the safety switch to the rear of the transmission gear box.
5. Start threading your new switch into the gear box by hand. Tighten it with your wrench. Plug the wiring harness into the back of the switch.
6. Reconnect the negative battery cable. Remove the jack stands and lower your 300D to the ground.