I am having a strange problem. My top and roll bar switches will remain lit after starting, and it prevents the window switches from working. If I disconnect & reconnect the battery it resolves temporarily, but comes back. All fuses are good. Any ideas where to start?

 

Does the roll bar switch activate the roll bars. Does the roof still go up and down?

 

No, the windows, top & roll bar are all inoperable. The windows will go down with the fob, but not the switch, and when you try to open the top they will remain up. If I disconnect & reconnect the battery, everything works perfectly

 

My (very) non-expert opinion is that it could be one of the sensors on the roof mechanism,.

When you reconnect the battery, without touching the roll bar or roof switches, do the windows work?

 

Highland doc........The W208/A208 is one of the best vehicles (e.g. from a drive train prospective) that MB has produced.

However, for luxury/convenience, the A208's (e.g. cabriolets) were only produced with power roof operation (e.g. along with a procedure to, manually close the roof, in the event that the power roof was inoperative).

I'm very familiar with the A208 power roof system and have suggested numerous repairs (e.g which, for good shade tree mechanics, has been 95%+ successful in power roof repair, for short money).

At this time, your power roof roof controller, connected to interior CanBus, is seeing intermittent faults, which upon ignition off and on again, are cleared (e.g until they re-appear again).

Fortunately, MB provided a power roof built in 'self test capability' (e.g. when you turn on ignition, the S84 power top switch should only illumination briefly, during the test).

If it remains on and/or blinks is explained in the below document.




However, based on what you have described (e.g., both the enter console power roof operating switch and dash roll-bar switch being illumined), I believe you'll have to examine each of the power roof and roll-bar actualization's, at the point of specific point of failure, as already posted

Lastly, after 20+ years, IMHO everything regrading, additional DIY diagnostics, regarding operation/repair of the power roof, has already been covered.

 

That’s what’s frustrating, there doesn’t have to be any actualizations. I can reset the battery, leave the top in place (up or down), and leave the windows in place (up or down), and I still get the fault in 1-3 days. I’ve checked circuit 30, and tried a manual reset the top with an open/ close. I did find the plunger with the roller on the edge of trunk lid is broken. Don’t know what the part is or does, or if it is related

 

In your situation, the repair is going to somewhat frustrating, because your malfunction appears intermittently.

Specifically, when a power roof malfunction occurs, the soft top controller will store an error code. When you disconnect the vehicle battery, circuit 30 power, which is always connected to the controller is removed and the malfunction is erased, the power roof operates properly, until the malfunction again reappears. However, when you remove the battery power, you'll also have to synchronize the power windows, reset the steering angle and radio code.

Therefore, standard diagnosis and troubleshooting techniques will only apply when the power roof is in the malfunctioning state.

The power roof controller is fused in 5 places. In fuse block F4, located inside the trunk, there are 4 fused circuits. Specifically, the always present circuit 30 power is fused by the 15A fuse in position 11, the pump motor is fused by the 40A fuse in position #13 and each rear window motor are fused positions 10 and 12. Additionally, in fuse block F1, located in the engine bay, circuit 15 power, which is only supplied to the controller by turning the ignition switch, there is a 5A fuse in position 15.

When checking fuses, never just trust by just viewing the sight glass, also pull the fuses and check that the blade contacts and socket do not have any corrosion, which would provide additional resistance to passing the required power to successfully operate the control module. Also by just pulling the circuit 30 fuse to clear the soft top malfunction code might be more convenient then disconnecting the vehicle battery and having to perform the additional aforementioned resets.

In your initial post you mentioned that when your roof malfunctions, both the center console soft top operating switch and dashboard roll-bar switches, remain continuously illuminated, when not being pressed while the the ignition is on, which is not correct. The soft top operating switch should only illuminate briefly, for one or two seconds while it performs the built in test capability and then turn off and the roll-bar switch should flash on/off for around 10-15 seconds and then turn off.

In addition to the possible causes for, one or both of the operating switches remaining continuously illuminated while not being pressed (e.g. as shown in the document in post #5), the controller is not receiving the confirming signal indicating that the roll-bar has not been completely retracted or the trunk lid is unlocked. If either condition is present, by design, the required clearances to prevent possible damage to the roof system may be insufficient and operation of the power roof will be prohibited.

 

My switch, clk320 cab 2000, remains illuminated permanently, but was never a problem until recently when the operation of the top and headrests started to become erratic, and later stopped working completely.

when I tried to open the top the windows would go down but nothing further.

in the end it turned out to the the relay next to the hydro pump. Easy test was to temporarily swap with the fuel pump relay as they are the same.

but does not fully sound like your issue.

 

Would the broken plunger located on the edge of the trunk lid have anything to do with it? I noticed the plunger with a wheel on the end opposite the trunk light off switch is broken. Does this signal that the trunk is closed?

 

No.

As shown below, the S88/2 trunk lid lock switch is a component of the S15/1 truck release assembly. Note: Diagram only shows it's pigtail and connector.

 

I removed the plunger & ran the part number. It’s the vacuum actuator. The hunt continues!

 

The central locking system's vacuum actuators, which are basically electrically controlled values, are usually directly attached peripheral components to the lock/unlock assembly (e.g. door locks). However, the A208 cabriolets have the actuator located separately on the trunk lid, to prevent the possibility of a collision between an open trunk lid and the lid of the soft-top compartment.

Specifically, the N52 roll-bar/soft-top operation control module, cyclically supplies the information "SOFT TOP CLOSED", "SOFT TOP UNLOCKED" or "SOFT TOP OPEN", via the CAN data-bus, to the A37 pneumatic system equipment pump / combi-function control module and as soon as the message "SOFT TOP UNLOCKED" is received, any remote (e.g. key fob, or center console trunk release) operation will no longer be performed. However, the trunk can still be opened using the mechanical key.

I've previously suggested examining each of the roof/roll-bar controller actualization's when the roof malfunctions (post #5), as well as if the controller has not confirmed that the roll-bar is not been completely retracted, both the top and roll-bar switches will simultaneously illuminate.

However, rather then guess, the discussion, methodology and included documentation within posts, #207 though #227, at https://mbworld.org/forums/clk-class...ailures-9.html should assist with your hunt.

 

So I have the exact same problem roof/windows will work fine for a few days then one day when ignition is switched on the roof switch stays illuminated (without being pressed) and all the windows/door mirrors/roof will not work. I have worked out rather then keep disconnectiong the battery I just turn off the key and in the boot fuse box F4 remove fuses 11 & 13 which is for the roof control module and one of the rear windows. Replace these then turn the ignition on and the fault is cleard Its easy for someone to say oh its the control box not getting a signal but how do you find/measure these inputs !!!!

 

Can you advise of a good (not too expensive) ODB2 fault code reader which will highlight roof problem codes and also parking senser codes? I have a bluetooth Carista ODB2 reader which works with the Iphone but this returns no faults found even though the roof switch is permenantly illuminated.

 

See post #2 here .

 

I am having the same problem with my 2001 CLK320 cab. Occasionally, now more often, when starting the vehicle, the top switch is illuminated and top, windows and mirrors are inoperative. Disconnecting the battery clears the issue for the day or longer, but then it returns. I have not read that anyone has solved this problem. Any success other that making power reset easier?

 

I used to have trouble with my 2003 CLK430, but had done quite a bit of work on it and have resolved top and headrest issues. 1) refill the hydraulic tank in the trunk. 2) replace or repair leaking convertible top cylinders

 

Just updating my top issue. The problem is: top, windows, mirrors and roll bar intermittently inoperative when starting up the vehicle. Once I reset the fault by temporarily pulling rear fuse box fuses 11 and 12, the top system functions perfectly. It started happening about 3 months ago and now happens about 50% of the time. Top control switch and Roll bar up/down switch stay illuminated after startup. I replaced the top control module and no improvement. Reading through multiple threads here, I decided to try bridging the "roll bar down" switch since I had to reset the roll bar when I purchased the vehicle. It had been deployed by an inexperience repair shop that did not disable it prior to lifting the vehicle. What a job that was! So I thought I may have jostled the switch or otherwise damaged it. But it has not helped. I thought it might be the trunk closed switch, but the trunk release button on the console is not illuminated. It does illuminate when the trunk is released, so I assume the switch is working properly, correct? The windshield header "top locked" switch also seems to be working since it correctly indicates the top is open when unlocking the front header (when the system works). Any other suggestions to check before I take it to a repair shop and spend big bucks for a diagnosis of this intermittent problem?

 

Can you validate whether the issue is correlated to the interior CANBUS module? CANC is what it is sometimes called. I’ve heard it can be an issue sometimes. How many items from the attached list are inoperable simultaneously?

 

I don't think it is the CANBUS module. Top, Windows, Mirrors, and rollbar are inoperable when my top switch and roll bar switch stay illuminated after startup. I am now investigating the lid pull down lock switch and found that the two switches work, but the connector was not fully seated. That may cause the top to be inoperable. I seated it correctly and will now wait through a few trials to see if that worked.

 

So far all of the switches I have checked that need to be engaged at step 0 of top down operation are working. Here is the information that I tested today. I reset the Top computer by pulling fuses 10.11.12 and tested that all was working. I then shut off the car and waited 15 minutes to turn on the ignition: all tested Okay per the Top switch light. I tested every 15 minutes and the top indicator lamp continued to turn off in 2 seconds indicating all testing okay for 2 hours. Then I tested every half hour and all Okay until 5 hours later when the fault re-appeared. All this time the vehicle was not started and the top was not activated, yet the failure returned! No switches were touched or wiring moved! Is there some Time related factor in the controller?
I already replaced the controller. Help please!

 

Check out this thread for a w208 with similar issues.

https://www.peachparts.com/shopforum...-problems.html

Included are some tips/tricks for diagnosing and/or finding root cause. Items noted are that any one “bad” module on the CANBUS circuit could be causing the failure. Sequentially disconnecting each (door units can be suspect, due to water intrusion) can help to find which is root cause.

 

Okay. I will try this tomorrow. This connector is accessed by removing the passenger side door sill plate and pulling back the carpet, correct?

 

Pulled the sill plate and removed the passenger side carpet to reveal the wiring conduits. Looked inside them, but I don't see any connector in there. Do I need to remove the kick panel as well?

 

Since I did not hear back from anyone, I tore into the right front kick panel area today. To get to the CAN/BUS connector you must remove the sill panel (3 clips on the weld flange), carpet (just lift out,) under dash hush panel (3 philips screws), and kick panel (one philips screw under a cover in the middle of the panel and 2 clips on the door opening weld flange). Pic 1.



Then you can unclip the wiring bundle cover and expose the mass of wiring through the area (pic 2).



I found the bus connector at the bottom of the front corner (pic 3).



There is enough wire to pull it up and out in the open (pic 4)



I finally got the cover clip off of the connector by lifting the tabs on the ends and prying it sideways. I removed connector one (lower control panel) by pulling it quite hard after not finding a release tab and reset my top. Now we will see if the problem is cured or go on to the next connector. Anyone else who has done this trial and error method would be welcome to comment.