Refer to Figure 1: Installation overview. The blue box at the right represents the SLK fuse box. The blue box at the left represents the SLK Combination Control Module (CCM). The red box represents the BVRC control unit.

Figure 1: Installation overview

Installation consists of the following steps:

1. Install the fuse and relays in the fuse box.

2. Route the fuse box wiring to the control unit.

3. Tap into the CCM wiring harness.

4. Connect the fuse box wiring to the controller.

Each step is covered in the instructions that follow.

During the installation, you’ll need to attach wires to four binding posts in the car, splice four connections in a wiring harness, and cut two wires and make connections to each end. A person with average mechanical skills can do the job. Installation is similar in complexity to installing a car alarm or remote starter, so if you’re not comfortable doing the installation yourself, you should be able to find a shop that can do it for a reasonable price.

Tools

You will need the following tools for installation:

Tool	Use
7mm, 8mm, and 10mm metric sockets socket wrench long extension	Installing relay wiring in the fuse box
Phillips screwdriver	Removing and installing interior panels
Wire cutter wire stripper insulated terminal crimper	Cut and splice connection in the fuse box and at the Combination Control Module (CCM)
Pliers	Installing self-stripping electrical tap connector
Narrow (3/16”) blade screwdriver	Attaching wires to control module connector
T-25 Torx wrench	Removing and installing the passenger side panel (optional)

Recommended tool

Combination wire cutter, stripper, and insulated terminal crimper. Available at most automotive, hardware, or home center stores in the electrical department.

Getting Started

Locate the radio code. You’ll need this at the end of installation.

Disconnect the negative terminal of the battery.

Warning!

The battery must be disconnected to avoid working on live circuits. A short circuit with the battery connected could cause damage and injury. Do not attempt installation without disconnecting the battery.

Fuse Box

Locate the fuse box. Facing the rear of the car, the fuse box is at the upper right of the engine compartment.

Open and remove the fuse box cover.

Remove the top of the fuse box by releasing the tabs at the left, front, and right sides of the fuse box.

Lift the fuse tray part way out of the fuse box. The fuse tray is secured by a pair of tabs at the front of the box. Grasp the front lip of the fuse box and pull forward slightly while lifting the front of the fuse tray upward. You may need to release one side at a time. Once the front of the fuse tray is released, the tray can be pivoted up and lifted partially out of the fuse box. See Figure 2: Fuse box.

Figure 2: Fuse box

Locate the four binding posts at the rear of the fuse box.

Refer to Figure 3: Fuse box wiring diagram for the next steps. There are five steps to complete fuse box wiring. Note that the items in the diagram which are supplied with the Vario Roof Commander are illustrated in white.

Figure 3: Fuse box wiring diagram

Step 1

Locate the second binding post from the left, labeled 1 in the diagram. It will have several red wires connected to it.

Remove the nut securing the red wires. Leave the wires intact. Add the following three wires with ring terminals to this binding post:

1. The large red wire with ring terminal connected to one of the BVRC relays.

2. The large red wire with ring terminal connected to a second BVRC relay.

3. The red wire and ring terminal connected to the BVRC fuse.

Replace the nut and tighten it.

Step 2

Locate the third binding post from the left, labeled 2 in the diagram. It will have several pink wires with red stripes connected to it.

Remove the nut securing the pink wires. Leave the wires intact. Add the large yellow wire with the larger ring terminal to this binding post. Replace the nut and tighten it.

Step 3

Locate the rightmost binding post, labeled 3 in the diagram. It too will have several pink with red wires connected to it.

Remove the nut securing the pink wires. Leave the wires intact. Add the large yellow wire with the smaller ring terminal to this binding post. Replace the nut and tighten it.

Steps 4 and 5

Locate SLK fuse 37. Beneath this fuse, locate the pink wire with red and blue stripes. Cut this wire about 4” from the fuse. Strip about ¼” of insulation from the end of each wire (about 20 gauge). Crimp a female bullet connector onto the wire that leads to the fuse using an insulated-terminal crimp tool. Crimp a male bullet connector onto the wire that leads down into the bottom of the fuse box.

(Should you ever decide to remove the Bipes Vario Roof Commander, you can simply plug these two connector s together to restore the original wiring.)

Plug the white wires from the third BVRC relay into the connectors that you just crimped.

Step 6

Locate the relay at the rear of the fuse tray. (If your vehicle has two relays, locate the relay with wires attached to it that are colored black with yellow stripe, black with green stripe, red with yellow stripe, and red.) Beneath the relay, locate the black wire with yellow stripe.

Using a self-stripping electrical tap connector, attach the BVRC black wire to the SLK black/yellow wire about 4” from the relay.

To use the tap connector, first slip the connector over the SLK wire to be spliced. Next, insert the BVRC wire into the connector. With the wires carefully aligned, squeeze the metal connector with pliers. Close and lock the plastic flap. Refer to Self-stripping electrical tap directions in the Appendix.

Final fuse box steps

From inside the passenger compartment, locate the black panel under the dash above the pedals. Remove the two screws securing this panel and remove the panel. See Figure 4: Under dash panel.

Figure 4: Under dash panel

From the top of the fuse box, thread the gray cable with the black, red, and clear wires through the bottom of the fuse box into the passenger compartment. Visibility can be improved by shining a light up from the passenger compartment into the fuse box.

Lay the BVRC relays and fuse into the bottom of the fuse box.

Carefully replace any wires in the fuse box that you may have disturbed during this part of the installation.

Replace the fuse tray by inserting the rear end into the slots at the back of the fuse box, and then pivot the front of the tray downward until it snaps in place. Take care not to pinch any wires in the fuse box.

Replace the top of the fuse box by snapping it in place.

Replace the fuse box cover.

Route the wiring

Remove the left and right console side panels (Figure 5: Center console side panel). To remove each panel, first remove the vent using a Phillips screwdriver. Turn the plastic fastener ¼ turn counterclockwise, then remove the vent. Remove the screw that is exposed after the vent is clear, and then remove the panel.

Figure 5: Center console side panel

Thread the gray cable under the carpet towards the center console. Take care not to interfere with the accelerator pedal. Thread the cable from one side of the console to the other side, routing it near the firewall.

Replace the under dash panel. Replace the console side panels.

CCM Wiring

Remove the black panel under the glove box. To remove this panel, first remove the two screws near the glove box door. Then, slide the panel backward to free the front lip. Slide forward and down to remove.

Grasp the top of the carpet and pull it back. Remove the white foam from behind the carpet.

Locate the large wire bundle to the upper right (Figure 6: CCM wire bundle). Don’t do anything with this bundle yet; we’ll get back to it momentarily.

Figure 6: CCM wire bundle

(Please note that this photo was taken after the yellow wire to the left had already been spliced into the bundle.)

Under the hood, locate the box which houses the Combination Control Module (CCM). This box is located next to the battery.

Remove the cover of this box by sliding the locking tabs or by loosening the four Phillips head screws (the screws remain attached to the cover), depending upon your particular model. See Figure 7: Combination Control Module.

Figure 7: Combination Control Module

To complete the CCM wiring, each wire in the bundle must be located by both color and connector location. Wires cannot be located by color alone, as in some cases there is more than one wire of the same color combination in the bundle.

Locate the CCM, which is the module closest to the battery. Note the bundles of wire which run across the top of the module towards the rear of the car. Following these wire bundles, note that they run down through the bottom of the box housing the CCM and into the passenger compartment.

There are at least two alternatives for making the required connections to the CCM: at the CCM, or under the dash.

CCM connection

Leaving the wire connectors at the top of the CCM in place, remove the CCM by unfastening the clip at the side. Next, using the connector diagram (Figure 10: CCM connector diagram), locate each connector pin by number and confirm the wire color. Make each connection in turn. When finished, route the wires down through the bottom of the CCM box into the passenger compartment. A simple tool such as a coat hanger and masking tape may be helpful.

Under dash connection

You may want to use a helper for this method.

First locate each wire at the top of the CCM, and then trace it down into the passenger compartment for positive identification. You will need to remove the black plastic wrap fastening the bundle to the carrier at the top of the CCM and loosen the fabric wrap around the bundle to trace the wires. You do not need to remove the fabric wrap; just loosen it. Work from inside the CCM box and from under the dash.

Select one wire at a time. Note the pin number and color combination of the selected CCM wire (refer to Figure 8: CCM wiring diagram). Next, using the connector diagram (Figure 10: CCM connector diagram), locate the connector pin by number and confirm the wire color. Then, trace this wire down into the passenger compartment. A helper observing from inside the passenger compartment while you gently tug on the selected wire can readily locate the desired wire in the bundle. Mark the wire by wrapping a piece of tape around it.

Cut and splice connection

(Note: If you do not want to enable the ‘speed limit’ function of the BVRC, you can omit this step.)

Having located the green wire with white stripe connected to pin 74 of the CCM, cut the wire. Strip about ¼” of insulation from each end of the wire (about 20 gauge). Crimp a female bullet connector to the end of the wire that runs down into the wire bundle away from the CCM. Plug the violet wire from the BVRC control module into this connector. Crimp a male bullet connector onto the wire that leads up to the CCM. Plug this wire into the yellow wire from the BVRC.

Warning!

Operating the top while moving presents a potential safety risk. Visibility is restricted while the top is in operation. The convertible top can be damaged if it is operated while the vehicle is moving. The top should not be operated in high winds or over bumpy surfaces while the vehicle is moving. No warranty for safe or damage-free operation of the convertible top while at any speed is expressed or implied. The user assumes all responsibility for safe operation and for any damage or injury that may result

Do not make this connection if you are not willing to assume this responsibility and risk.

Figure 8: CCM wiring diagram

Figure 9: CCM oriented as in the CCM connector diagram

Figure 10: CCM connector diagram

Spliced connections

Using a self-stripping electrical tap connector, attach each of the three BVRC wires (blue, white, green) to their corresponding wires in the CCM bundle. The orange wire is not required for most installations. Refer to the section Optional lock connection later on.

Replace the cover on the CCM box under the hood.

Ground connection

Remove the panel on the outside wall below the glove box. To remove the panel, carefully pry the oval cover from the center of the panel. Remove the exposed torx screw, and then remove the panel.

Locate the ground stud (Figure 11: Ground stud) behind the panel. Remove the nut. Fasten the brown wire from the BVRC control module to this stud. Replace and tighten the nut.

Figure 11: Ground stud

Optional lock connection

Consult the Owner’s Manual Alarm section before making this optional connection. This connection is not required for most installations.

Pull the carpet back from the foot well on the right side of the car. Remove the white foam piece. Using a 10mm socket wrench, remove three plastic nuts that secure the metal panel. Lift this panel out and fold down to expose the wiring. See Figure 12: Foot well panel.

Figure 12: Foot well panel

Locate the connector marked by the red arrow. The connector has 4 pins, numbered 1-4. (The numbers can be seen if the connector is separated.) Locate the black wire at pin 3. Using a self-stripping electrical tap connector, attach the orange wire to the black wire. Strip ¼” of insulation from the opposite end of the 20 gauge orange wire and attach it to the green connector per Figure 8: CCM wiring diagram.

Reinstall the panel, nuts, foam, and carpet.

Connecting the fuse box cable

Strip about 3” of the outer jacket from the gray fuse box cable. Remove the foil shield surrounding the wires. Cut and discard the bare shield wire. Strip about ¼” of insulation from each of the three 18 gauge wires (red, green, and clear) in the cable. Insert each wire in turn into its proper location in the BVRC control module connector. Tighten the screw securing each wire.

Plug the BVRC connector into the control module.

Secure the control module behind the panel near the ground stud or behind the metal panel under the foam. You may want to use double-sided foam tape or self-stick Velcro fasteners (not supplied). Take care to see that there is no strain on the wires leading into the control module, so that they will not work loose under vibration. Secure these wires with plastic ties.

Replace the panels, foam, and carpet.

Reconnect the cable to the negative terminal of the battery.

Turn on the radio and enter the radio code. Reset the clock.

If the BAS/ESP warning light illuminates after reconnecting the battery, recalibrate the steering angle sensor. Start the engine and, while idling, turn the steering wheel lock to lock (full left then right). The warning lamp should extinguish.

LED System check

Basic system functionality can be checked via the LED on the BVRC control module front panel.

When power first applied to the BVRC, the LED begins blinking once per second. This indicates that the BVRC is active. After a short period of time, the blinking stops. This indicates that the BVRC has entered its low-power ‘sleep’ mode to conserve battery power. The LED resumes blinking when the key is turned to position 2, or when a button on the remote is pressed.

If the LED does not light and extinguish as described, check the wiring and fuse. Refer to the Troubleshooting section.

Operational Note

A fully-charged SK battery has enough reserve power to operate the Vario roof several times with the engine (and battery charging system) off. However, repeated operation of the Vario roof in a short period of time may deplete the battery and overheat the hydraulic unit. Mercedes-Benz has thoughtfully provided safety measures to avoid damage to the Vario roof systems, excessive drain on the battery, and warn when the battery voltage is too low to operate other systems in the vehicle. Repeated operation of the Vario roof in a short period of time may result in one or more of the following conditions:

· Blinking indicator lamp in the center console Vario roof switch

o Battery voltage too low

o Hydraulic unit over temperature

· BAS/ASR warning lamp

o Battery voltage too low

Enjoy your Vario Roof Commander, but enjoy in moderation.

Troubleshooting

Basic troubleshooting consists of verifying the wiring connections.

You will need an analog or digital voltmeter to perform these basic troubleshooting steps. A voltmeter can be purchased at many automotive, hardware, or home center stores, or at Radio Shack, for $20 or less. Set the voltmeter to read DC volts, and if not an autoranging type, set it to the 20 volt or next higher scale. Consult the voltmeter operator’s manual as needed.

Remove the fuse from the BVRC fuse holder.

Disconnect the wiring harness from the BVRC control unit by unplugging the green connector.

Replace the fuse, leaving the green connector unplugged.

Note the screws in the top of the connector, which are used to secure the wires at the connector. You will verify connections by touching the voltmeter probes to these screws.

Power connection check

Touch the negative (black) voltmeter probe to the screw corresponding to the brown wire. Touch the positive (red) voltmeter probe to the screw corresponding to the red wire. You should read about 12 volts (11.1 to 12.9) on the voltmeter. If not, check the power (red) and ground (brown) connections of your installation.

Fuse box connections check

For the next steps, remove the covers from the fuse box. Locate your voltmeter near the fuse box and attach the negative voltmeter lead to ground. Refer to Figure 3: Fuse box wiring diagram.

With the ignition switch off and the key removed, attach the positive voltmeter lead to binding post #2. An insulated alligator clip, supplied with most voltmeters, is recommended. Caution: power (12 volts) is present at nearby terminal #1 and the terminal next to it. Take care not to unintentionally short these to ground. If unsure of yourself, disconnect the negative lead to the vehicle battery first, make the voltmeter connection, then reconnect the battery lead. Position the voltmeter so that you can view its display from the green BVRC connector.

Momentarily ground the clear wire at the green BVRC connector. You can do this using a short piece of wire, touching one end of the wire to the screw corresponding to the clear wire and the other end to chassis ground. Or, you can temporarily remove the clear wire from the connector and touch it to chassis ground. Touching it to ground should engage the BVRC relays and activate the accessory devices in the car (such as the radio if left on), so don’t be alarmed. With the clear wire grounded, verify about 12 volts on the voltmeter. This should return to 0 volts when the clear wire is not grounded.

Repeat the above test for binding post #3.

If either test fails, check the relay wiring at the fuse box.

Replace the covers on the fuse box.

Remote connection check

For the next steps, place the voltmeter near the BVRC green connector. Attach the negative voltmeter probe to ground. Either touch and hold the lead onto the brown screw, or use an alligator clip to attach the lead to a ground point on the car (bare metal or a ground lug – one with brown wires attached. The positive voltmeter probe will be touched to one of the screws corresponding to a particular wire identified by its color. ‘Black wire’ means touch the probe to the screw corresponding to the black wire.

Touch the positive voltmeter probe to the black wire. With the ignition switched off and the key removed from the ignition, verify about 12 volts. Press the Unlock button on the key fob and verify that the voltage momentarily drops to 0 volts. This will happen only for a fraction of a second. Depending upon the response time of your voltmeter, you may not see 0 volts, but may see the voltage display change briefly, then return to about 12 volts. Check the black wire connection if you do not see 12 volts and 0 volts as described.

Switch and indicator lamp connections check

Stow the luggage cover so that the convertible top will not operate. Touch the positive voltmeter probe to the green wire. With the key in the ignition and the ignition switched turned to position 2, verify about 12 volts. Push the convertible top switch forward, and verify 0 volts. Check the green wire connection if you do not see 12 volts and 0 volts as described.

Touch the positive voltmeter probe to the white wire. With the key in the ignition and the ignition switched turned to position 2, verify about 12 volts. Push the convertible top switch backward, and verify 0 volts. Check the white wire connection if you do not see 12 volts and 0 volts as described.

Touch the positive voltmeter probe to the blue wire. With the key in the ignition and the ignition switched turned to position 2, verify about 12 volts. Push the convertible top switch backward and hold so that the indicator light flashes. Verify that the voltage drops to near 0 volts when the lamp is lighted. Depending upon the response time of your voltmeter, you may not see 0 volts on the meter’s display, but you may see the voltage drop and rise as the lamp flashes. Check the blue wire connection if you do not see 12 volts and 0 volts as described.

Optional lock connection check

Touch the positive voltmeter probe to the orange wire. Verify about 12 volts. Insert the key in the door lock and turn the key as in locking the vehicle. Verify 0 volts when the key is turned. Check the orange wire connection if you do not see 12 volts and 0 volts as described.

Vehicle Speed Sensor (VSS) check

You may need a helper for this step, as you must drive the car to perform this check. Don’t crash while looking at the voltmeter!

Remove the violet wire from the green connector. Connect the positive voltmeter lead to the violet wire using an insulated alligator clip. If you have not already done so, connect the negative lead to chassis ground using an insulated alligator clip.

Start the car and drive it very slowly – hardly moving at all. The voltmeter should switch between near zero volts and near 12 volts. You must be moving quite slowly to observe this behavior. Check the violet wire connection if this test fails.

There is no easy test for the yellow wire connection.

When done checking

Remove the BVRC fuse before inserting the green connector into the BVRC control unit. Replace the fuse.

Caution: The green connector must be plugged into the BVRC for vehicle speed sensing (vario roof, wipers, and door locks at speed) to be operational.

Appendix

Parts identification


Female bullet connector	Male bullet connector	Self-stripping electrical tap connector

Self-stripping electrical tap directions


1. Slip connector onto running wire.	2. Insert tap wire.

3. Close metal clamp completely.	4. Close insulating cover.