The Mercedes-Benz "E-series" debuted in 1986, using the Mercedes W124 chassis platform. The first Mercedes-Benz E320s utilised naturally aspirated, 3.2-litre dual-overhead-cam six-cylinder engines capable of producing 217 horsepower. The 1998 and newer models feature Mercedes-Benz's Flexible Service System that alerts the driver when it's time for regular service maintenance. "Service B" maintenance schedule includes changing the oil, checking the brake pads, checking the tires, lubricating drivetrain components and various other visual inspections. If you perform these maintenance tasks yourself, you'll want to reset the service interval warnings after completion.
Climb into the vehicle and close the driver's door.
Switch the ignition key to the second position. Within four seconds of switching the ignition key to the proper position, press the "0" button located on your left-side instrument panel four times in rapid succession.
Turn off the vehicle's ignition.
Press and hold the "0" button while turning the vehicle's ignition back to the second position. Continue holding the "0" button for 10 seconds or until the display reads "SERVICE IN".
Release the "0" button, turn the ignition to the off position and start the vehicle to verify that the service message has cleared.