There is a water leak next to the throttle pedal - WO3.

[Black_raven]

There is a water leak entering via the plastic card located next to the throttle pedal. W03 Saloon. Currently unable to verify it, therefore I decided to share it here to see if anybody has seen this situation before. There is now heavy rainfall here, yet the automobile has never had any water leakage even during intense downpours. Can the blockage of the bonnet vents by leaves or other debris result in water drainage issues? I am now making an educated estimate till I get the opportunity to examine it further.

[Needsnewtyres2]

In the W203, I believe the issue arises from a deteriorated grommet on the bonnet release cable, where it passes through the bulkhead.
It is only accessible when paired with a newly manufactured cable assembly.
Indeed, if the bonnet drains are obstructed, all possibilities become uncertain.

[Black_raven]

Your advise about the bonnet release cable grommet was accurate and helpful, my friend. It was detached from the lip that forms a seal with the panel. I currently do not have any available time to remove components in order to replace the cable and grommet. Meanwhile, I have successfully sealed it with silicone. There are currently no other leaks from any other sources, therefore we hope that the existing leak is the only issue. On a tempestuous and rainy day, a test was conducted to see whether anything could remain dry. The test was successful, as the object in question managed to stay dry. Exhale.

[Black_raven]

The leak recurred and was not in the region of the bonnet release cable. I am still uncertain about the source of its entry. Once again, on the left side of the vehicle. I have thoroughly cleaned all drain hoses and applied silicone on all plastic edges to prevent any potential fractures in the plastic, which might allow water to flow through. Currently, I am eagerly anticipating further precipitation in order to do a test. Can someone who has a W03 saloon/coupe kindly provide photographs of the driver's side bottom windscreen area and the inner wing of their vehicle? I would want to compare them with mine to ensure that everything is in proper order. I just had my vehicle undergo its MOT inspection last Saturday, exactly one week ago. On Monday, my rear glass broke. I had it replaced on Friday. Then, on Saturday night, I had a leak into the driver's footwell during what was perhaps the most intense period of rain we had here. Discuss a brief period of unfortunate circumstances.

[Black_raven]

Although I previously attempted to fix it with silicone, the leak has resurfaced in the same location in recent days. The location of the component seems to be next to the primary fusebox, in close proximity to the brake master cylinder. The most probable cause is the seal of the bonnet release cable, however my query is. Could someone provide guidance on the proper procedure for removing the main fusebox in order to get access underneath it, please? The vehicle in question is a 2005 Saloon model of the WO3 C class, specifically designed for right-hand drive operation. I would appreciate it if someone could provide me with information on this topic. I have not yet had the opportunity to get into it and examine it. If I discover a suitable platform to upload the video of the leak, I will distribute it to enable others to see it.

[bentleygt77]

I have an idea and I want to clarify that I am not questioning your diagnosis, but might it be possible that the A/C evaporator drain is obstructed? The evaporator is located in the inside of the fascia and is responsible for cooling the air. Similar to a chilled window, the moisture present in the air undergoes condensation and then drops into a conveniently positioned tray below. The tray is equipped with an overflow pipe that directs excess liquid to the lower part of the automobile. If the passage is obstructed, the water spills into the inside of the automobile.

Coincidentally, a well functioning drain is often the cause of an enigmatic pool of water under the vehicle.

[Black_raven]

The issue with the A/C drain is not pertinent to the leak I am experiencing. Once I figure out the process of entirely removing the fuel box, as well as removing the inner arch, plastics, and soundproofing beneath the steering wheel in the region of the bonnet release cable, I will be able to reach the issue and resolve it. By bisecting a circular rubber seal, it is possible to consistently and completely fit it into panelling around a cable, thereby sealing it. I have personally used this technique for many years without encountering any issues. In this case, it implies that there is no need to replace the whole bonnet release cable, which would be very impractical considering the amount of time it would take.I own a video capturing the genuine occurrence of the leak. Once I get the opportunity, I will allocate time to shoot further photographs. Regrettably, I am now in the midst of a series of nightshifts, so I am trying to find some time to work on it before the week concludes. I am astonished by the absence of any online articles with remedies or photographs pertaining to this issue and the origin of the leak. The main focus is on obstructed drainage systems and the process of speculating about the cause and determining appropriate actions to address the issue. However, there is a complete absence of any visual representation on the internet. This is certainly a prevalent issue. An automotive technician specialising in panel beating and bodywork examined the vehicle recently and indicated that the deteriorated seal responsible for water ingress is located under the fusebox. The subsequent action would include eliminating the object and commencing the process of capturing images with the camera. I will attempt to upload the footage of the breach into Photobucket immediately.

[Black_raven]

Currently occupied with work, but will have an opportunity to go into this at a later time. Does anybody have information on the WIS paper that provides instructions for removing the ECU fusebox located next to the master brake cylinder? I am able to locate the removal procedures for all other modules except for this particular one. 😞

[EtherealWanderer]

Have you successfully resolved this issue? Despite cleaning all the drain lines, I am still experiencing a rain puddle on the driver side.
Assistance in any kind would be very appreciated.

[BENZE220AMG]

Have you inspected the bonnet release cable as mentioned previously?

[EtherealWanderer]

Thank you for your response. Not as of now. Is it located underneath the fuse box?
Should I begin from the inside of the cabin or the engine compartment?
I am completely unaware of where to begin in my search for photographs or videos.

[nimbuye5]

Inspect the drain tubes in the cowl for any obstructions caused by leaves. I lack knowledge on the W203, however this issue is often seen in other models.

[Black_raven]

The issue is with the rubber grommet that secures the bonnet cable as it passes through the bulkhead. The object becomes distorted and finally develops significant leaks. I attached a long and slender tube to the nozzle of a sealant gun and meticulously filled it completely with sealant. (without the need for disassembling the fusebox or any other components). Indeed, the sealant will solidify and maybe shift its position. I have completed it on two occasions. The issue has been resolved. I have never had any water infiltration again. A friend who has his own automotive repair business briefly examined it and advised me on what actions to take.