2009 Mercedes CLS-Class Owner's Manual - Page 161

Controls in detail Driving systems Parktronic system malfunction There is a malfunction in the Parktronic system, if only the red distance segments illuminate and an acoustic warning sounds. The Parktronic system will automatically switch off after 20 seconds and the indicator lamp 2 in the Parktronic switch 1 comes on. X Have the Parktronic system checked at an authorized Mercedes-Benz Center as soon as possible. If only the red distance segments illuminate and no acoustic warning sounds, the Parktronic system sensors are dirty (e.g. dirt, ice, snow and slush) or there is an interference from other radio or ultrasonic signals (e.g. truck air brakes, car wash, or jackhammers). The Parktronic system will automatically switch off after 20 seconds and the indicator lamp in the Parktronic switch comes on. X Switch off the ignition. X X X Clean the Parktronic system sensors (Y page 244). Switch on the ignition. or Check the Parktronic system operation at another location to rule out interference from outside radio or ultrasonic signals. Z 159