How to Replace the Climate Control Unit in a 1994 Mercedes Benz C220

1. Unhook the C220's negative battery cable using a wrench. This keeps you safe from shock and prevents an electrical short circuit.
2. Inspect the bottom edge of the radio to find two Phillips screws. Remove them and set them in the cup holder.
3. Insert your Mercedes radio removal keys into the slots on the sides of the radio. Push them in firmly to engage them, and then pull the radio forward. Unplug the two connections from the back of the radio and set the radio unit aside.
4. Inspect the radio cavity to find two Phillips screws. Remove them and set them in the cup holder. These secure the trim panel.
5. Grasp the bottom of the trim panel and pull it off. Move the trim panel to the side. It's not necessary to unplug the connections on the back of the panel. Now you have access to the climate control unit.
6. Remove the four Phillips screws from the climate control unit. Slide the unit out and unplug the connections from the rear. Move the old climate control unit out of the way.
7. Plug the connections into the new climate control unit. Insert it into the dash. Insert and tighten the four screws to mount it.
8. Position the trim panel back in place and push it firmly against the dash. Insert and tighten the two Phillips screws inside that secure the bottom edge of the panel.
9. Plug the radio connections back in. Insert the radio back into the cavity. Remove the Mercedes radio keys from the slots. Replace the two screws beneath the radio. Reconnect the negative battery cable.