Specs Cars

1. Wiggle the steering wheel while turning the key. If there is pressure on the steering wheel that holds it on the lock pin, the key will not turn. A locked steering wheel is not the source of the problem if the steering wheel turns but the key still does not turn.
2. Start the car with a spare key. If the spare key works but the main key does not, you obviously have a bad main key. A replacement key for the E320 costs around $200 as of January 2011. You will need a valid registration and title to complete the purchase.
3. Place the key in the ignition and listen for a clicking noise. If both the spare key and the main key fail to turn, and you hear a clicking noise when you insert the key into the ignition, you most likely have a bad ignition switch. Visit a Mercedes-Benz dealership or a repair shop to confirm this diagnosis. A new ignition switch for the E320 will run you about $1,000 as of January 2011.

1. Fold the wiper arm away from the windshield. It will lock with the wiper pointing away from the glass.
2. Move the wiper blade so it is at a right angle to the wiper arm.
3. Check the arrow on the wiper arm and remove the blade from the retainer in that direction.
4. Place the replacement blade in the retainer and slide it into the slot in the opposite direction of the arrow.
5. Position the blade so it is parallel to the wiper arm and fold it back to its normal resting place on the windshield. Repeat process for the other wiper blade.

1. Obtain the radios five-digit access code from the radio code card supplied with the vehicle. If the code card is unavailable, the access code can be obtained from a Mercedes Benz dealership.
2. Turn the E320 key to position 1 or 2 to enable the radio power and turn on the radio. CODE will appear in the radio display.
3. Enter the radio code using the alpha-numeric keypad on the right side of the radio face.
4. Press the OK key to confirm the entry and activate the radio.