S212 E350 enters limp mode when towing

[LunaCraze]

My 2013 350 AMG/Sport Est has shown an intermittent issue occurring about every 200 miles while towing our huge caravan. The trailer seems to pull the automobile backward on the road. The safety system inoperative warning appears, resulting in limp mode activation. Cease operations and resume; everything should function well for a further 200 kilometers approximately. No codes have been recorded. Attempted to deactivate the SRS system; nonetheless, it persisted in its operation. I sometimes downshift and maintain higher RPMs on travels to address any EGR/DPF issues. Unfortunate outcome 😞 I appreciate the automobile; but, I may need to contemplate an other tow bar if I cannot resolve the issue. The tow bar was installed by a professional, despite his extensive prior experience.

[Workerat]

Are you certain that the problem does not pertain to the caravan? Does it have AL-KO ATC? The system engages the caravan brakes upon detecting swaying, which may be influencing the car's response.

Is this caravan a single or double axle, and what is its Maximum Technically Permissible Laden Mass (MTPLM)? What is the towing capability shown on the vehicle's plate? What is the duration of your use of this combination?

[MutanX]

Has the vehicle undergone remapping? If executed poorly, increased fuel pressure may cause the car to enter limp mode under load.

[LunaCraze]

My supposition was based on the fact that the caravan is equipped with ALKO ATC. Consequently, I disabled the SRS via the onboard display. The caravan weighs 1803 kg and has a dual axle, whereas the car's specifications indicate a capacity of 2100 kg; nevertheless, it is now operating at about 92%, which is suboptimal. This is a new tow vehicle, since I previously hauled with huge SUVs. I have significantly enhanced it by meticulous packing, since the caravan dominated the vehicle. Nonetheless, I like the vehicle but need a resolution to the limp mode problem.

[LunaCraze]

Greetings and gratitude. I acknowledge your remark, but the vehicle is very satisfactory on its own. It is applicable just while towing. The towing capability is exceptional.

[Workerat]

Isn't SRS the system for airbags and seatbelts?

A dual axle is inherently more stable than a single axle, hence it ought to perform well even at a rather high match %. Aside from the limp mode issue 😄 ATC should be used seldom, since it may adversely affect the brakes; within 12 months, my vehicle wore down a set of pads to the extent that one drum was scored and required replacement, despite my not seeing any intervention.


What are the tire pressures for both the vehicle and the caravan? Does the automobile manual include towing suggestions, including the suggestion to elevate tire pressures to the maximum rated levels (full load/high speed) to enhance resistance to lateral forces?

[Workerat]

I presume you own an adequate nose weight and that any substantial items are positioned centrally. Do you lack a bicycle rack on the rear of the caravan? Are there items you may transport in the vehicle instead of the caravan, such as the awning? Have you verified the precise weight of the caravan, since it is very simple to inadvertently exceed the weight limit.

[Workerat]

Neglected to include ... which may not have resulted in any apparent problems while towing with a larger/heavier truck.

[JetstreamJay]

The caravan seems to be engaging its brakes, which may be confounding the car's safety systems and perhaps triggering limp mode; however, I cannot ascertain why '200 miles' would be relevant. Did you want to refer to ESP rather than SRS?


Was the vehicle 'coded' appropriately when the towbar was installed? To my knowledge, this is a procedure performed by MB, however I am uncertain about the age at when it became relevant. Opinions are divided on its need. Technology, indeed 🙂

[JetstreamJay]

😁😆