2020 Honda Odyssey: water leaks into the cabin

Filed Oct 26, 2026 · Acceleration, Driver assistance · IL

Over the course of 3 days, cruise control and lane assist systems would shut off and messages would display about adaptive cruise control, lane keep assist, lane departure warning, and collision avoidance system not working. Sometimes a transmission problem message would also become active. Sometimes the messages would be present at startup but other times the systems would show up green on the display and then the systems would shut off while driving causing the vehicle to suddenly slow down in highway traffic. The root issue seems to be a broken or malfunctioning multipurpose camera for the driver assist system. The camera has not been replaced yet to verify but related codes are active based on a code scanner and symptoms match what is expected for the camera failure. The vehicle is 6 years old with 99,400 miles at the first occurrence of the issue and does not have any windshield damage or signs of water leaking that would contribute to a failure. My primary concern is that the software completely disables cruise control when the camera for adaptive cruise and lane keep assist fails causing the vehicle to suddenly slow down rather than allow normal cruise control to continue operating and display the warning messages.

Filed May 26, 2026 · Electrical · TX

My 2020 Honda Odyssey power tailgate has failed due to water intrusion through defective rear body seam sealer, a known manufacturing defect. Water leaked into the rear driver's side panel and damaged the power tailgate control module, making the rear door inoperable. I took my vehicle to the Honda dealership, who confirmed this is a factory defect related to improper seam sealing. The quoted repair cost is over $8000. Honda has declined to cover this under warranty. This defect poses a safety risk as the tailgate can open unexpectedly while the vehicle is in motion. I am aware of a pending class action lawsuit involving 2018-2021 Honda Odyssey models with this same defect. No recall has been issued. I am requesting thr the federal safety agency investigate and compel Honda to issue a formal recall.

Filed May 5, 2026 · Body, Electrical · MA

I own a 2020 Honda Odyssey and I am currently having a safety issue with the power tailgate. Upon inspection by my Honda dealership, my vehicle requires a new power tailgate control unit and floor harness and my roof rail and clips need to be re-sealed and replaced. It was discovered that due to the break in seal the connectors corroded due to a water leak.In April of 2026 I received multiple warning messages on my dashboard. The first was Power tailgate problem and the second was keyless remote problem. At first I noticed my car continuously beeping while driving along with the warning on my dashboard. I attempted to turn the vehicle off to see if it would reset, but it did not. I attempted to open and close my tailgate. I could only open my tailgate with the push button on my dashboard. I had to manually close my tailgate due to my buttons on my car and my key fab failing to work. Next while driving, I could hear the locking mechanism on my tailgate continuously locking and unlocking. Of course this particularly concerned me because I have 3 young children and their safety as well as mine was in danger. It was unclear if my tailgate was going to open while driving. Such an action could potentially cause a serious threat or harm to myself, my family or other vehicles on the road.

Filed Mar 6, 2026 · Body, Electrical · MD

Tailgate control module damaged by water leaking from faulty rear body seam seals on left top of vehicle Doors would lock and unlock on their own while driving and tailgate signaled it was open but never unlatched Manual tailgate opening/closing did not work at all Constantly beeped when unlocked and alarm went off randomly All electrical activity drained battery and made vehicle undriveable; tow was necessary First sign was "power tailgate problem" light on dash 5 days before vehicle battery was dead Honda charged for and replaced Tailgate control module and recommended an outside company to repair leak issues; outside company confirmed issue and noted repairs for same issue on similar models

Filed Jan 15, 2026 · Body, Driver assistance · TN

All of my ADAS systems were disabled due to a water leak. The repair required the dealership to hire a "leak doctor" and then replace a module in the rear tailgate. My vehicle showed an alert on the dash that each of the ADAS features were disabled, auto high beams were disabled, and I could not turn the vehicle off by pushing the start/stop button once, I had to use a procedure that forced the vehicle to shut down. My interior dash lights flickered, I'm not sure if the headlights worked. As the interior dried out, the flickering occurred less frequently. I was able to drive the vehicle to a Honda dealer for repairs.

Filed Dec 12, 2025 · Driver assistance · VA

The tailgate control module has been water damaged and needed to be replaced twice. My local Honda dealership was unable to correct the issue and stated that it is due to a water leak in the frame of the vehicle/tailgate. The dealership has identified the tailgate control module as the cause of the electrical issues causing the battery to die, and advanced safety features to malfunction. Warning lights came on for break system problem, lane departure mitigation system problem, and many other systems all caused by the tailgate control module being water damaged from a leak in the frame.

Filed Dec 5, 2025 · Electrical · NC

Dash has warning light showing "Power Tailgate Problem", and power tailgate will not function. The next day there was heavy rain, and the dash had a flickering warning showing the tailgate was open. This also caused the interior lights to flicker on and off as the tailgate open warning was flickering on and off. I returned the van to my home for fear that the tailgate would open automatically while driving down the road. I had the tailgate control module replaced on February 27, 2025 for this same issue, which was due to a tailgate seal leaking water onto the tailgate control module that shorted the module. This is now the second time within less than one year this same module has shorted out. This is a known issue with a class action lawsuit already filed against Honda that should result in a recall. The potential danger of the tailgate opening while driving makes this minivan not usable to transport my kids for fear of their safety.

Filed Jul 2, 2025 · Electrical · FL

The power tailgate control module has been failing. That makes power tailgate problem light come on, than the tailgate beeps and eventually fails. It unlatches itself, and won't latch until the control module has been replaced. My control module has been replaced 3 times, and now a week later after being replaced my tailgate has failed again, the power tailgate problem light is on and tailgate won't open. I was told by Honda dealership that theres a water leak that's causing it. Along with replacing the unit they are trying to seal it but it's still failing.

Filed Mar 21, 2025 · SC

Tailgate Control Unit failed due to water entering through the seals of roof seal which resulted in damaging the functionality of the tailgate. Failure to open. I noticed one day that the tailgate would not open (the back hatch). My Honda dealership got the vehicle in rather quickly (One week). Dealership stated they have never seen this and requested repairs of over a thousand dollars. After further research on the issue, I noticed that there are multiple class-action lawsuits with multiple law firms. This is not an isolated issue. However, I am glad that the dealership was able to get my vehicle in and fixed in an appropriate amount of time. The worry was that just one day, the back tailgate quit working and there was no manual way to open the vehicle in case of collision, fire, or water incident and used as an escape route. With multiple class action lawsuits on the same incident, I believe this incident needs to be followed up on. Solutions: Revist the type of seal Honda is using. Move the control unit to a different location within the vehicle so the control unit will not become waterlogged and damaged. Lastly, provide a manual unlocking and opening mechanism for escape out of the rear tailgate if vehicle is involved in a collision, fire, or water event.

Filed Mar 8, 2025 · Body · OH

The power tailgate continues giving issues. I made the first repair about 1.5 years after purchasing as a new vehicle purchase. Now a few years, after the first repair, I', seeing the same issue. The power tailgate stops working and makes all the warning lights on my dashboard light up and drains my battery. During the last repair, the tailgate power unit was replaced as water gets into the compartment and causes damage. Initially it affected the driving assistance, the power steering system and lights as they were all acting up, with the dashboard full of warning messages, when the tailgate initially stopped working.

Filed Feb 22, 2025 · Body, Seat belts · NC

Top left rear exterior seam/seal on the top of the roof, under the black strip that runs front to back is leaking inside the left inner side/panel of the trunk, leaking water into all electrical components (break/turning lights) as well as the left rear seatbelt mechanism, soaking seatbelt, rendering it unusable. Could be a potential fatality in case of an accident.

Filed Feb 18, 2025 · Body, Electrical · AL

I have had 3 Power Tailgate modules fail due to water leaks in the rear panel or window of the vehicle. I have had 2 leaks repaired and two modules replaced within a 6 month period (June '24 and December '24). 6 weeks later (Feb 14, 2024) have had the 3 module fail due to water intrusion following a heavy rain.