Computers/Controls - Malfunctions Of Various Power/Control Unit
Malfunctions of various control units and/or on-board power supply problems caused by water in the control unit tray under the driver/front
passenger seat (dislocated, pinched or leaking condensation hose)
Topic number L183.00-P-052510
Version 2
Design group 83.00 General
Date 02-28-2013
Validity All Mercedes-Benz cars
Reason for change Remedy adapted, validity adapted
Complaint:
Water that enters into the control unit tray under the driver/front passenger seat can damage the control units installed there and complaints may be
received about the functions associated with these control units.
Problems with the on-board power supply voltage may also occur.
Cause:
The condensation hose (right/left) on the A/C housing may either be dislocated, pinched/crushed (water collects in A/C housing) or leaking, resulting
in water entering the interior.
Remedy:
If the condensation hose (right/left) is dislocated, push it all the way back onto the outlet fitting of the A/C housing and check for tight seating by
pulling gently. If necessary, use a cable tie to additionally fix the condensation hose in place. Never use soapy water or silicone spray to install.
If the condensation hose (right/left) is pinched/crushed, it can be checked for free passage as follows:
1. Use the operating unit to set maximum cooling on both sides.
2. On the vehicle underside, check whether water emerges from the condensation water drains. If no water emerges, the hose is blocked. In this
case, reposition the hose correctly to ensure free passage or replace the hose if it is damaged.
Invoice the damage with reference to the appropriate damage code..
Mercedes-Benz A220 2020 Page 469
