A238 2017 E Class Convertible Roof Problem
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A238 2017 E Class Convertible Roof Problem
Dear all,
Experiencing some issues with convertible roof not working and wondered if anyone else has experienced the same and what was the cause.
The instrument cluster displays “open/close roof top completely”. Nothing happens when I press the roof open or close switch.
Scanned rear control module and have one active fault code which returns after clearing. It reads B22A449 ‘Soft top control’ has a malfunction. There is an internal electrical fault.
The trunk also doesn’t open and has to be opened either by pulling the manual release cable or by actuating the rear trunk motor using diagnostic software. I think this is a safety precaution because it thinks roof is not fully opened or closed.
What I have done so far:
- Noticed battery was weak so replaced
- Checked connections at rear control module. All seems okay. If I disconnect the rear control module then the error on instrument cluster goes away and allows me to open the trunk.
- Confirmed using live data that the switch is “working” when I press open/close even though nothing happens. Strangely, also none of the other buttons on the switch panel are working either such as the button to open all windows and even the button that opens the storage compartment under arm rest.
I am leaning toward having to replace the rear control module but they are quite expensive so wanted to know if anyone else had any similar experiences and what else to check before resorting to this?
Part number for my rear control module is A2389007900. Can’t seem to find any used ones for sale and wondering whether this part has now been superseded?
Thank you so much
Experiencing some issues with convertible roof not working and wondered if anyone else has experienced the same and what was the cause.
The instrument cluster displays “open/close roof top completely”. Nothing happens when I press the roof open or close switch.
Scanned rear control module and have one active fault code which returns after clearing. It reads B22A449 ‘Soft top control’ has a malfunction. There is an internal electrical fault.
The trunk also doesn’t open and has to be opened either by pulling the manual release cable or by actuating the rear trunk motor using diagnostic software. I think this is a safety precaution because it thinks roof is not fully opened or closed.
What I have done so far:
- Noticed battery was weak so replaced
- Checked connections at rear control module. All seems okay. If I disconnect the rear control module then the error on instrument cluster goes away and allows me to open the trunk.
- Confirmed using live data that the switch is “working” when I press open/close even though nothing happens. Strangely, also none of the other buttons on the switch panel are working either such as the button to open all windows and even the button that opens the storage compartment under arm rest.
I am leaning toward having to replace the rear control module but they are quite expensive so wanted to know if anyone else had any similar experiences and what else to check before resorting to this?
Part number for my rear control module is A2389007900. Can’t seem to find any used ones for sale and wondering whether this part has now been superseded?
Thank you so much
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