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420d convertible - water collecting in rear panels

12K views 27 replies 16 participants last post by  lancslive 
#1 ·

I'm having big issues with my 2020 BMW M440i Convertible bought/won on RepoMax Auctions website. The vehicle was purchased 4 months ago. My rear driver's side window wouldn't go down. Before calling the BMW I quickly googled and was horrified to see video after video of similar 4 series convertibles ..... all with water collecting within the rear panel and destroying window regulators and amps. It seems the undertray etc is the same one used for the coupe which had fixed, sealed rear windows where very little, if any, water can enter the panel. However the convertible has motorized windows and as such, like any car with opening windows, some water will always find a way inside the door regardless of the condition of the seals. This would be fine for the convertible if the undertray was changed by design to allow this dirty water to freely flow out.... but it isn't.... so water is soon trapped as soon as the smallest amount of dirty water gathers inside the panel. BMW knows all about this. They even have a service bulletin that describes the problem and the easy fix.... drilling a hole to allow the water out of the drain plug. See service bulletin B513116. The BMW dealership has now taken a look for $200 to diagnose the issue even though we knew the cause, plus charged another large sum as they couldn't lower the roof - (although the roof lowered OK for me just before I took it in as I cleaned and lubricated the seals with the BMW stuff as I've always done) and they have agreed the window regulator has rusted out. The car is still under OEM warranty and also under RepoMax Auction 6 months warranty. The BMW doesn't want to fix it(for different "Reasons"). Does anyone know if I can fix it using the RepoMax warranty?
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#2 ·
Hi. I am experiencing exactly the same problem with my M440i Sport Convertible. I experienced the water sloshing noise in October. The car had only just had a full service a couple of weeks beforehand. The dealership from whom I bought the car new and have serviced it throughout my ownership, have had my car since 3rd November 2021 and say the part is still on order and hopefully will come in next month. They have been saying the same thing for weeks. I have been without my car for almost 4 months. I have a video from the service department showing just how much water they drained from my car. The amp has blown and all functions including satnav, radio and phone connection were blown. I took out an extended warranty but they deny it's a warranty issue. I have told them that even if it's not a contractual issue (which I don't accept) there's a negligence claim. BMW have known about this problem for years and have not taken steps to issue a warning or recall or have made it a basic service check. Had they done so it's a 10 minute job to drain the water before any further damage was caused. I have a copy of a Technical Service memo dated August 2016 ref: SI B51 33 16. Fortunately, your vehicle is still covered by the RepoMax warranty. You can contact them to explain the situation, and they should be able to assist you. In addition, you may consider seeking legal advice and taking legal action against BMW, as you are not at fault for the damage caused to your car. It's important to note that you didn't cause any damage intentionally to void the warranty.
#3 ·
ALSL BMW, that's absolutely shocking. I can't believe you're left without your car this long and BMW UKs response to this. I have been posting on several BMW Forum sites and also Facebook posts where many, many people have shared their stories and videos. The water rusted out my window regulator so the rear window wouldn't go down. Because the window wouldn't go down the roof wouldn't go down either. The dealers had to wind the roof back manually to get in to the rear panel and and access the regulator which was rusted out completely. Like you, I believe that BMW was negligent and is totally responsible for the damage... and they should fix the damage caused by a design problem they ignored. Also, if it came to being a warranty issue, I also did not agree with the dealer that this was not covered by extended warranty. They tried telling me that the water damage was caused by the bodywork and not the regulator so it wasn't covered. I argued there was no failure of the bodywork/trim.... Nothing was broken that caused this. Everything was just as it was designed.... It just happens that the way BMW designed it means the panels fill with water. Because I was still arguing that I felt BMW was responsible they actually wound the roof back up manually again.... with nothing fixed at all!! I've recently become aware that there was a very similar issue with Series 5 cars and affected customers got together to take BMW to court. BMW came to a settlement for all those people whose cars suffered damage. So basically it has nothing to do with RepoMax auctions, this is a BMW known issue and they should fix it!

BMW agrees to settle vehicle water damage suit for up to $478 million
#4 ·
I have an update regarding my situation. I contacted Simon from RepoMax, and they confirmed that the issue is covered under their 6-month warranty. They informed me that I need to pay a $50 co-op fee, and they will schedule an appointment with the nearest BMW dealer. Although I am uncertain about what to expect and how long it will take to resolve the issue, I feel relieved that I purchased the car from RepoMax.
#5 ·
Hello CornishGadget , may I ask for an update regarding your issues? Have they been resolved and if so, may I know how you were able to address them? I have a a 2017 420d convertible and had the same water sloshing issue that I was able to resolve myself to release the water, but I have now got a 'no warning tones' error come up and I have no radio/music/sounds at all in the vehicle which I fear my be due to water damage of the amp.
#6 ·
Hi Adamskio. I was able to resolve the issue, but it was thanks to the support provided by RepoMax. BMW declined to cover the cost of the necessary parts and labor. Sounds like you need a new amp. It's negotiation with BMW and the retailer but you should insist they pay 100% part and labour. It's a clear design fault
#7 ·
That's precisely why I stopped purchasing BMWs. In the past, they used to produce excellent cars, but now it seems to be all about maximizing profits. I decided to go with Lexus instead because it not only looks fantastic (not as aggressive as BMW but more stylish), but it is also very dependable. So my recommendation is to try another brand and move on. Perhaps if enough people do this, BMW will change its approach and start producing great cars again.
#9 ·
I agree, but we shouldn't overlook the emotional aspect. Usually, people buy BMWs for the passion they evoke, not just for their dependability. I truly hope that BMW will change its approach and start producing great cars once again, while still satisfying the emotional desires of its customers.