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Created: 9 Oct 2007

Last Updated: 29 Dec 2007

V1.1 9th October 2007

This article covers installing COMAND APS in the facelifted W203 C class and W209 CLK class. The facelift happened for Model Year 2005.

North American vehicles do not get COMAND APS, they get MCS-II. so this does not apply to  US vehicles. Please do not try putting a Euro COMAND APS into a vehicle for North America as you will find there are no navigation map DVDs that work.

Of course if you are bringing a North American C/CLK to Europe (etc) then this article is useful as you will have to install a European COMAND APS system if you want European maps for navigation.

Please remember that C class COMAND-APS and CLK class COMAND-APS units are not interchangeable - they are shaped differently.

Tools needed.

  1. Torx TX20 driver
  2. Pulling Hooks (W140 589 0233 00)
  3. Plastic Wedge (W110 589 0359 00)

Parts needed.

Amount Part Number Description and Notes
1  See my COMAND-APS parts document at
1  A001 820 7675 Retrofit GPS antenna
1  A211 820 00 88 Retrofit antenna cable adapter
1  Velcro strip To hold GPS antenna in place


Parts Notes

Here is a eBay search tool that will find you a COMAND unit, although if you want to purchase a genuine warrantied unit from the UK, I suggest looking at 

Here is a picture of the retrofit GPS antenna and adapter.

Mercedes GPS retrofit antenna picture

Note also that you should not remove the protective paper from the visible side of the antenna.


Installation consists of the following steps: -

  1. Remove old head unit
  2. Install GPS antenna
  3. Install COMAND
  4. Reassemble
  5. Have dealer Code COMAND and Cluster with Star DIagnosis

1) Remove old head unit

To remove the audio unit on the facelifted Mercedes W203 C and W209 CLK class, you have to access the four torx screws that hold it in place.

This is simpler on the CLK than the C, as you do not have to remove the air vents.

a) Remove gear knob and surround.

Pull up the edge of the gearknob, and then turn the locking ring at the bottom of the gearknob anti-clockwise (i.e not the natural way you would expect) half a turn and pull the gearknob upward to remove.

Picture of the locking ring.

W203 C and CLK gearknbob release catch

b) Remove panel around gear knob.

This is done by simply pulling it upwards from the front, and then the rear.

c) Remove ash-tray.

Release the catches and pull upwards.

Here is a picture of the ashtray and the catches.

Mercedes C and CLK ashtray release catches pictures

d) Remove aircon surround.

Look up under the panel through where the ashtray was. You can either see two screws and two catches or four screws.

- if you have 4 screws remove the two that are at an angle, otherwise release the catches. You can then remove the lower control panel, and see the 2 torx screws that hold the bottom of the audio unit.

Here is a picture with the screw on the left that must be removed highlighted.

W203 C class aircon panel screws

Remove the aircon controls and panel, which reveals the lower screws for the audio system.

Aircon panel removed on W203 C class mercedes picture

e) C Class only: - remove vents

The vents are held in by 2 screws at the bottom corners and two clips at the top corner. To see these screws and clips the vents have to be moved completely to the top and then completely to the bottom.

To allow the vents to move, there are catches that must be released with a small screwdriver.

The catch to make it move to the top is shown in this picture, the catch to make it move to the top is two sections above.

W203 vent release lock

After the vent has been moved to the upper position, you can see the lower screws. Loosen these but not too far or they'll drop out.

W203 vent screw

Then move the vent to the lower position (don't forget to release the locks) to view the top catches and using the pulling hooks, pull the catch in and the vent out.

Here is a picture of the catch on the vent when the vent is removed so you can see how it works.

W203 top vent catch picture

f) C Class only: remove top two screws holding the Upper Control Panel (UCP),

W203 UCP screws picture

and remove the UCP to show the top two screws of the audio unit.

UCP removed picture

g) CLK class - open the coin tray next to the upper control panel, slide your finger in behind the edge of the UCP and pull - it will pop out quite easily, revealing the top two screws of the audio unit.

h) Remove audio unit

Remove the four screws holding the audio unit, and remove the audio unit.

i) More pictures

Here is what the CLK looks like with those panels and the audio unit removed.

Mercedes CLK (W209) facelfit audio system removed picture

2) Fit GPS antenna

Attach adapter cable to antenna and using velcro fix it on the top of the plastic ledge to the right side of the air-vent, with the hole in it facing upwards and the velcro on the metal side.

Here is a picture of the GPS antenna installed.

W203 GPS antenna installed picture

3) Re-assemble

Connect the GPS antenna and the main power connector, along with the black antenna cable and the yellow antenna connector if your vehicle has it.

Ensure the COMAND unit is pushed in well, with cables dropped below to ensure good airflow around the rear, slide up the latches and screw in the screws

Power on the unit, it should turn on, although it will probably turn off again after a few seconds of displaying the Mercedes star logo - this is normal for units that have not been configured with Star Diagnosis.

Re-assemble the other panel work.

4) Have MB dealer code unit and Cluster.

The dealer must code the AGW (which is in the COMAND on the C/CLK), specifically telling the system what is on the fibre optic bus (or if nothing is on it), and checking that the AGW flash software is up to date. I suggest that the dealer perform the 'Inital Startup' sequence process in Star Diagnosis.

The cluster will also have to be coded to enabled Navigation system menus and to allow it to take the time-of-day from the COMAND system.

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