Door control module
Door control module (in WIS) or Electric Seat Adjuster Switch (in EPC) is electrical part responsible for several tasks. When looking for part in catalogs, you may need to add color code to end of the part number (e.g., A22082106587C45).
Functionality
The door control module in itself is a pretty dumb device. All key presses are sent over CANBUS to SAM. SAM then broadcasts message to all modules and module which understands the message acts appropriately (whether lighting up some bulb, engaging seat heating, moving seat, etc.).
DCM is responsible for:
- External mirror:
- Lighting up mirror turn signal light
- Lighting up mirror courtesy light
- Mirror heating
- Mirror angle altering
- Mirror fold-in
- Receiving signal from infrared receiver
- Engaging door power close
- Opening door window
- Receiving signal from window control switch
- receiving signal from trunk open switch
- Receiving signal from mirror control switch
- Powering door handle LED
- Powering door courtesy light
- Receiving signal from seat regulation switch
Power for driver side front DCM is controlled by fuse X.
Location
DCM is located in door trim held by plastic clips.
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Connectors
Seat Adjustment
Front seat adjustment
All W220s have front adjustable seats. The seat adjustment switches are located on the front doors. Use of buttons:
- (1) Head restraint height
- (2) Seat height
- (3) Seat cushion tilt
- (4) Seat cushion depth
- (5) Seat fore and aft adjustment
- (6) Seat backrest tilt
Rear seat adjustment
In vehicles equipped with option code ?? the switch can be used to adjust rear head restraint.
In vehicles equipped with option code ?? the switches can be used to adjust rear:
- (1) Seat bench fore and aft adjustment
- (2) Head restraint fold/place upright
In vehicles equipped with option code ?? the switches can be used to adjust rear:
- (1) Seat fore and aft adjustment
- (2) Seat height
- (3) Head restraint fold/place upright
Front passenger seat adjustment from rear
Vehicles equipped with option code 247 have two additional buttons (buttons (1) and (2)) on the rear DCM behind front passenger seat, which can be used to adjust front passenger seat.
None: Adjusting the passenger seat position from the rear is not possible if you deactivate the operation of the rear door windows (override switch in driver's door).
Seat heating and ventilation
Seat heating
All W220s are equipped with seat heating feature for front seats.
Seat heating has three modes:
- Rapid heating (two lamps on)
- Normal heating (one lamp on)
- No heating (lamps off)
The system switches from the rapid heating mode to normal heating mode after approximately five minutes. The seat heating will be automatically switched off after approximately 30 minutes.
Seat ventilation
Vehicles with option code 401 are equipped also with the seat ventilation feature.
The blue indicator lamps on the switch show the ventilation level selected.
Seat ventilation can be activated manually with the SmartKey in starter switch position 1 or 2.
The driver's seat ventilation can be activated to the highest level automatically by the summer opening feature.
Rear seats are heated in vehicles with option code 872. In vehicles with option code 402 rear seats are heated and ventilated.
Note: If one or all of the lamps on the seat ventilation switch are flashing, there is insufficient voltage since too many electrical consumers are switched on. The seat ventilation and heating switches off automatically. The seat ventilation and heating will switch back on again automatically as soon as sufficient voltage is available.
Heated and/or ventilated seat buttons
Seat ventilation functionality does not depend on the specific DCM used. Appropriate buttons are not part of DCM and can be bought separately.
It is possible to use heated and ventilated button for engaging heating on vehicle without ventilation. It is possible to use heated button on vehicle with seat ventilation, however, not all heating and ventilating states can be engaged.
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Memory seats
Memory seat function is determined by DCM itself. Even more, by controls board.
It has been tested that vehicle originally equipped with DCM A2208214179 in drivers doors can be replaced with DCM A2208211579 and memory seats will work out of the box. To mount DCM with memory buttons appropriate door panel with holes for memory buttons must be mounted. Alternatively, if memory functionality is not needed, one can replace front control board connected by wire with control board from A2208214179.
Mirror Adjustment
- Driver’s side exterior rear view mirror button
- Passenger-side exterior rear view mirror button
- Adjustment button
Mirror adjustment switch is not part of DCM, but connects to it.
Window control switch
Driver's door switch
For facelift vehicles driver's doors have part number A2208213179 (for both left hand and right hand drive vehicles). Although visually the same EPC lists part A2208213279 for vehicles equipped with remote trunk locking (option code 881).
Override switch
You can disable the following functions in the rear passenger compartment for instance when you have children riding in the rear passenger compartment):
- rear door window operation
- adjustment of front passenger seat from the rear (option code 247)
- cigarette lighter in rear
To activate slide override switch (1) to the right. A dot becomes visible. The functions in the rear are disabled.
Note: Operation of the rear door windows with the switches located in the driver's door is still possible.
Trunk lid switch
You can open the trunk from the inside if the vehicle is stationary. Pull remote trunk lid switch (2) until trunk begins to open. The trunk lid opens. The indicator lamp (1) comes on and remains lit until the trunk is closed.
You can close the trunk from the inside if the vehicle is equipped with option code 881. To close press remote trunk lid switch (2) until the indicator lamp (1) goes out and trunk lid is closed.
Other door switch
In all doors except driver's door, the switch with part number A2208213379 is used.
Using right hand drive DCM in left hand drive vehicle
It has been tested that RHD DCM A2208212179 installed on left side of LHD vehicle originally equipped with A2208214179 will work fine, however, the mirror controlling switch will not work and window controlling switch will be able open only driver's door window. Similarly, RHD DCM A2208211879 installed on left side of LHD vehicle originally equipped with A2208214979 will work fine, however, the window opening switch will open left side driver's door window.
Using left DCM on the right side
The physical location of DCM is programmed into DCM. E.g., if left DCM is connected to right side, the DCM will still move left seat.
Using pre-facelift DCM in facelift vehicle
Has not been tested.
List of door control modules
Early DCM had weak protection against moisture and therefore could be easily damaged if the door window was left open while raining. In later DCMs MB has improved protection against moisture. When looking for replacement DCM buy the latest compatible DCM in the category.
Facelift (from 30/09/2002)
Front Left
| Part No. | Front | Back |
|---|---|---|
| A2208214179 (left hand drive vehicles) | photo | photo |
| A2208211579 (left hand drive vehicles) | photo | photo |
| A2208214479 (right hand drive vehicles) | photo | photo |
| A2208212179 (right hand drive vehicles) | photo | photo |
Front Right
| Part No. | Front | Back |
|---|---|---|
| A2208214979 (left hand drive vehicles) | photo | photo |
| A2208211679 (left hand drive vehicles) | photo | photo |
| A2208215079 (right hand drive vehicles) | ||
| A2208211879 (right hand drive vehices) | photo | photo |
Rear Left
| Part No. | Front | Back |
|---|---|---|
| A2208216279 | photo | photo |
| A2208215779 | photo | photo |
| A2208212379 | photo | photo |
| A2208212779 (right hand drive vehicles) | photo | photo |
Rear Right
| Part No. | Front | Back |
|---|---|---|
| A2208216879 | photo | photo |
| A2208216379 | photo | photo |
| A2208212479 | photo | photo |
| A2208212879 (left hand drive vehicles) | photo | photo |
Pre-facelift (to 01/09/2002)
Front Left
| Part No. | Front | Back |
|---|---|---|
| A2208208710 (left hand drive vehicles, to date 29/07/1999, replaced by A2208218751) | photo | |
| A2208218751 (left hand drive vehicles, to date 30/06/2011) | photo | photo |
| A2208212958 (left hand drive vehicles, from date 30/06/2001 to date 01/09/2002) | ||
| A2208200110 (left hand drive vehicles, to date 29/07/1999, replaced by A2208219351) | photo | photo |
| A2208219351 (left hand drive vehicles, to date 30/06/2001) | photo | photo |
| A2208213358 (left hand drive vehicles, from date 30/06/2001 to date 01/09/2002) | photo | photo |
| A2208208910 (right hand drive vehicles, to date 30/06/2001, replaced by A2208219151) | photo | |
| A2208219151 (right hand drive vehicles, to date 30/06/2001) | photo | photo |
| A2208213158 (right hand drive vehicles, from date 30/06/2001 to date 01/09/2002) | photo | photo |
| A2208202610 (right hand drive vehicles, to date 30/06/2001, replaced by A2208219751) | photo | photo |
| A2208219751 (right hand drive vehicles, to date 30/06/2001) | photo | photo |
| A2208213758 (right hand drive vehicles, from date 30/06/2001 to date 01/09/2002) | photo | photo |
Front Right
| Part No. | Front | Back |
|---|---|---|
| A2208208810 (left hand drive vehicles, to date 30/06/2001, replaced by A2208219251) | photo | photo |
| A2208219251 (left hand drive vehicles, to date 30/06/2001) | photo | photo |
| A2208213258 (left hand drive vehicles, from date 30/06/2001 to date 01/09/2002) | photo | photo |
| A2208200110 (left hand drive vehicles, to date 30/06/2011, replaced by A2208219851) | photo | photo |
| A2208219851 (left hand drive vehicles, to date 30/06/2011) | photo | photo |
| A2208213858 (left hand drive vehicles, from date 30/06/2001 to date 01/09/2002) | photo | photo |
| A2208209010 (right hand drive vehicles, to date 29/06/1999, replaced by A2208218851) | photo | photo |
| A2208218851 (right hand drive vehicles, to date 01/09/2002) | photo | photo |
| A2208202710 (right hand drive vehicles, to date 30/06/2011, replaced by A2208219451) | photo | photo |
| A2208219451 (right hand drive vehicles, to date 30/06/2011) | photo | photo |
| A2208213458 (right hand drive vehicles, from date 30/06/2001 to date 01/09/2002) | photo | photo |
Rear Left
| Part No. | Front | Back |
|---|---|---|
| A2208214351 (to date 30/06/2001, replaced by A2208211558) | photo | photo |
| A2208211558 (to date 30/06/2001, replaced by A2208214958) | photo | photo |
| A2208214958 | photo | photo |
| A2208203310 (to date 30/06/2011, replaced by A2208210958) | photo | photo |
| A2208210958 (to date 30/06/2011, replaced by A2208214758) | photo | photo |
| A2208214758 | photo | photo |
| A2208200310 (to date 30/06/2011, replaced by A2208211358) | photo | photo |
| A2208211358 (to date 30/06/2011, replaced by A2208215158) | photo | photo |
| A2208215158 | photo | photo |
| A2208214551 (right hand drive vehicles, replaced by A2208218351) | photo | photo |
| A2208218351 (right hand drive vehicles, replaced by A2208215558) | photo | |
| A2208215558 (right hand drive vehicles) | photo | photo |
Rear Right
| Part No. | Front | Back |
|---|---|---|
| A2208214451 (to 30/06/2001, replaced by A2208211658) | photo | photo |
| A2208211658 (to 30/06/2001, replaced by A2208215058) | photo | photo |
| A2208215058 | photo | photo |
| A2208203410 (to 30/06/2001, replaced by A2208211058) | photo | photo |
| A2208211058 (to 30/06/2001, replaced by A2208214858) | photo | photo |
| A2208214858 | photo | photo |
| A2208200410 (to 30/06/2001, replaced by A2208211458) | photo | photo |
| A2208211458 (to 30/06/2001, replaced by A2208215258) | photo | photo |
| A2208215258 | photo | photo |
| A2208214651 (left hand drive vehicles, replaced by A2208218451) | photo | photo |
| A2208218451 (left hand drive vehicles, replaced by A2208215658) | photo | photo |
| A2208215658 (left hand drive vehicles) | photo | photo |
Resources
Making your own DCM control buttons: http://www.benzworld.org/forums/w220-s-class/1624796-seeking-rh-headrest-adjuster-button.html
Dissecting DCM (A2208214979)
Left-hand-drive right front DCM (without memory function) dissected. The process of disassembling did not cause damage - all parts pictured can be reassembled back.
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Dissecting DCM (A2208211679)
Left-hand-drive right front DCM (with memory function) dissected. The process of disassembling did not cause damage - all parts pictured can be reassembled back.
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