Comfort Roof Control Module for

  • BMW 3 Series Convertible (E93)
  • BMW Z4 Roadster (E89)


  • Further information and manuals for all products can be found on our web site

    w w w . m o d s 4 c a r s . c o m

    We explicitly point out that all functions of this control unit should be used only while exercising caution and responsibility. We can NOT be held liable for any damage or injury caused by installing or using this product.
    Important Information. READ BEFORE INSTALLING!
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    If you run into any problems after installing the module, please go over the manual again in great detail, clicking every photo for full size!
    We now have a full Knowledge Base with Support Ticket system available online at

    If you need to contact us, the best and fastest way to do so is by opening a support ticket there

    This module comes with our USB Field Upgrade and Configuration Port! We recommend connecting it to a computer BEFORE YOU INSTALL and using our support app "m4cconnect" to do a quick firmware update check. M4cconnect as well as all other information regarding USB update and configuration can be found at You can even configure and activate your favorite module functions and settings on screen before the module is installed in the car! It is a good idea to permanently install the USB cable with the module in the car, leaving the computer plug in an easily accessible spot for later use with a Wifi/3G/4G connected laptop.
    The green DATA LED signals a correct installation and shows the status of the module.

  • Ignition OFF: CAN bus and module are in low-power standby mode. This is normal.
  • Ignition ON: Either power connection or CAN bus connection is interrupted. Check the two wire taps for power and ground as well as the CAN connectors. Also make sure the CAN polarity is correct.
    LED either dimly lit or flickering erratically
  • A dim or flickering LED is an indicator for interrupted or missing POWER or GROUND connections. The module will get some leakage current from the CAN bus which causes the LED to stay dimly lit or flicker erratically. See previous paragraph about wire taps if applicable!
    LED permanently ON
  • Module is connected to CAN and power, but does not receive the correct data. Recheck all connections thoroughly. A VERY COMMON source of problems is reversed polarity on the CAN wires. Double-check the POLARITY and wire-colors of all connections!
    LED blinks
  • CAN bus is active, the module is connected correctly and ready for use.
  • Installation - Steps 1-3
    1. Turn ignition on and open convertible top to the shown position (service position), then stop. Now turn ignition off and pull key before continuing! From the right side, reach into the trunk and lift the luggage divider (1) into the upper position. Then remove plastic cover (2) by pulling toward the front of the car. It is only held in place by three spring locks.
    2. The spring locking mechanisms are marked here with arrows.
    3. Now pull up on the bottom of the carpeted piece to reveal two more spring locks (1). Remove the plastic plugs (2) and (3) to remove the whole carpeted piece.
    Installation - Steps 4-6
    4. Remove additional plugs (1) and (2) that hold the plastic cover in place. One (see arrow) is hidden right behind the trunk lid hinge. Remove the whole plastic piece.
    5. Underneath is another protective plastic cover. Lift it out to reveal a cluster of control units.
    6. The convertible top controller is white and easily distinguished by a bright green and a long black connector. Push down on the locking tab (1) while moving the lever to the left (arrow) to remove the black connector from the controller.
    Installation - Steps 7-9
    7. Remove the black plug from the top controller and replace it with the one from the SmartTOP wiring harness. Since the introduction of the plug and play wiring harness, the cloth tape does NOT have to be removed (as seen here) any more! IMPORTANT: Push the plug firmly into the socket so that the locking lever flips up and latches by itself. Don't try to use the lever to "pull" the plug into the socket. Otherwise some of the pins won't make contact and thereby prevent the top from working.
    8. Connect the original plug to the matching socket on the wiring harness (also making sure the lever locks into place). Connect the SmartTOP module to the plug on the harness. The green LED on the module should light up briefly (module starts up) and after a quick tap on the unlock button on the remote, should blink in a regular pattern (data bus activity). Put everything back together. We recommend leaving the USB cable installed and accessible for easy firmware updates or module configuration via laptop.
    9. The best way to stow the bulky harness and connectors in the tight space is shown here. This way the lid(s) can be reinstalled without problems.
    Installation - Step 10-11 - COMMON PROBLEMS AND SOLUTION
    10. When you insert the plug, you may hear 2 clicks. The first click is the pull bracket clicking into place. The second click is a mechanism along the side of the socket clicking into place (marked in the picture). If you use sufficient force when pushing down the plug, then both of these things will happen at the same time, Otherwise, you may have to push down on the socket with some force to get the second click. It a little awkward in there, so you may not get the right amount of force on the first push all the time. If the second locking mechanism is not properly in place, then there is a plastic piece on the side of the socket that will appear slightly bowed out. This means that your top will not work, but there will be a green led on the module, so at first glance, it looks like things are good. However, once you start hitting buttons on the remote, you will see the error led light up, and the convertible top will not be functional (door locks work though).
    11. If the above still doesn't help and the top won't work (green LED on steady with ignition on) this has been reported several times as the solution: Remove the black cap from the plug that is to be inserted into the original top control unit. Just insert the inside connector without the cap into the socket and press down hard to ensure it is all the way in. Retest top operation / check green LED for flashing pattern with ignition on.