mspreston

Hi, I'm new to MBWorld. I have a 2002 CLK 430 Cabriolet. The trunk doesn't work when the top is up (either from transmitter or console), but it works when the top is down. When the top is up, I don't get a beep signaling the completion of the cycle and the light on the trunk switch won't light. When the top is completely down and I get the beep, the trunk light operates and the trunk can be opened from either transmitter or console. Any help would be appreciated before I take to local dealer. Thanks.
Mike

Serndipity

The soft-top operation control module (N52) cyclically supplies the information "SOFT TOP CLOSED", "SOFT TOP UNLOCKED" or "SOFT TOP OPEN" to the CAN databus.

As soon as the message "SOFT TOP UNLOCKED" is received, the pneumatic system equipment (PSE), combi-functions (A37) no longer performs any remote trunk release operations.

A chime from the overhead control panel control module (N70) a at the end of each soft-top opening or closing operation, a signal is sounded for 1 s from the overhead control panel control module (N70), which confirms the correct implementation.

BTW, this interlock is by design, to prevent an open soft top case cover from colliding with an open truck lid.

During driving mode and with an incorrectly locked soft top, a warning signal sounds for 10 s.

Note: For further output of the warning signal, the system must first be reset (e.g. turn ignition "ON" and "OFF" again).

It appears that when you close the roof and lock the roof, with the locking handle, the Soft top "locked" (left) limit switch (S84/11) is not telling the controller that the roof has not been closed and locked (see enclosed thumbnail).

While this could be due to a faulty switch or wiring, dollars to doughnuts, the screws that fasten the switch to the windshield frame have loosened, such that the locking handle lever is no longer able to reach and properly actuate the switch.

mspreston

Very much appreciate your thorough, quick response. Your last solution makes most sense. On examining the left side of the latching mechanism, I noticed broken plastic pieces around the male/female latch. My assumption, forgive any male chauvinist implications, is that my wife attempted to close the top without releasing the center latch and possibly damaged the switch? The broken plastic pieces hint to this. How difficult is it to replace this switch?
Again, appreciate the help.

Serndipity

Although there have been a number of issues with the S84/11 screws loosening and just needing a simple re-alignment/re-fastening, I'm now somewhat perplexed by..........

"""""""On examining the left side of the latching mechanism, I noticed broken plastic pieces around the male/female latch. My assumption, forgive any male chauvinist implications, is that my wife attempted to close the top without releasing the center latch and possibly damaged the switch?"""""""

First of all, 'a release' of the latch, on closing, is not necessary and impassible (e.g. it's not required). Next, the S84/11 switch is behind the visor and a plastic panel, would not have produced the plastic pieces you note.

From which you're now now saying, I believe your locking latch mechanism itself (e.g. an issue with it's pivot point) is the culprit.

If so, there are some solutions.

You'l find them using via 'search', on the specific topic.

mspreston

I will check the S84/11 switch as well as the latching mechanism.
Many thanks and I will post my findings.

mspreston

Is there any diagrams to show how to replace S84/11 switch? The upper windshield panel has to be removed and I don't want to do any damage to tabs, clips, etc. Tried to get repair manual for CLK430 Cab, but only available for PC. I have MAC. Any leads or diagrams would be appreciated.

Serndipity

https://mbworld.org/forums/clk-class...hemselves.html

mspreston

I took apart the fascia on the top of the windshield and located the S84/11 switch. It was intact and not loose. I also tested the switch by opening the contact and heard a click elsewhere which lead me to believe the switch is working. I have a replacement switch but the lead is 76" long and leads down the pillar post and connects somewhere under the dash. Where does it connect? I was thinking of just plugging in the new switch and see if it sends the signal that the top is closed. Is there a switch at the base of the convertible back window to tell the system the top is completely up? Should there be a beep as soon as the convertible top glass is locked? Any help is appreciated.

Serndipity

In you 1st post, you said "The trunk doesn't work when the top is up (either from transmitter or console), but it works when the top is down. When the top is up, you don't get a beep signaling the completion of the cycle and the light on the trunk switch won't light. When the top is completely down and you get the beep, the trunk light operates and the trunk can be opened from either transmitter or console."

On our cabriolets, by design, to avoid the trunk lid from colliding with the soft top compartment cover, the trunk will not open, if the soft top is completely open or completely closed. The lamp in the trunk release switch, on the center console, is controlled by the (PSE) combi-functions controller (A37) and will always illuminate whenever the trunk is opened, using any method, including the manual key. Since your trunk opening, when your top is closed is disabled, the lamp does not turn on.


The power roof controller (N52), evaluates inputs from several position/limit switches to verify that the roof has been fully closed and locked and messages the PSE control module (A37), via the CANBus. Internally, the controller interrupts the switch being open (e.g. held at 12 volts through a pull-up resistor) or closed (e.g. at 0 volts because the switches short the voltage to ground). Additionally, as mentioned in my initial reply, the soft-top controller cyclically notifies the current status (e.g. SOFT TOP CLOSED, SOFT TOP UNLOCKED or SOFT TOP OPEN), to the PSE control module (A37) and the overhead control panel (N70) via the CANBus. If the message "SOFT TOP UNLOCKED" is received, the pneumatic system equipment (PSE) controller (A37) will no longer perform any remote trunk release operations.


As described in the S84/11 thumbnail (e.g. in post #2), when the soft top is locked onto the window frame, the contacts close via the lever of the locking handle and the soft top closed and locked circuit is switched to ground, notifying the N52 controller that the final stage of roof closure has been successfully completed.

The S84/11 switch wiring is routed through the A pillar, where it's connection to the wiring harness to the N52 is made. I'm not sure where the connectors meet, but my guess is behind the side kick panel. However, given that your inspection of the S84/11, found the mounting bolts secure and that the switch was being actuated by the locking handle lever, this, plus that the power roof will normally open and close, likely rules out an issue in this area. BTW, the most common problem with the S84/11 switch has been with the lever not closing the switch with enough force, such that when going over bumps, the windows might unexpectantly open.

However, a SOFT TOP UNLOCKED fault can also be due to locking signaling issues in prior stages of roof closure.

Another possibility is the soft top compartment cover closed switch S84/5 (e.g although the compartment is actually closed, the N52 controller has not received the appropriate input signal). Note: Because the case is hinged, the flexing of the wiring harness has been know to cause problems (e.g. broken wire, shorts). See https://mbworld.org/forums/clk-class...-failures.html

I've enclosed several thumbnails, that provide further details.