Diagsheet

2018 Honda Odyssey · symptom sheet

Water leaks into the cabin

  • 37owner reports
  • $1,000median quote
  • 0involved a crash

Newest report Aug 9, 2026 · checked Sep 9, 2026

330 of the 977 complaints on this car are about the electrical system. 37 of those describe water leak.

Tick what matches of 37 reports

3
17
8
4

What got replaced

Owners who name the part that was replaced mention the module (23 reports), the seal or weatherstrip (11 reports) and the drain tubes (4 reports).

Recalls and investigations

One recall on the electrical system covers the 2018 model year. A recall on the same system isn't always the same failure, so read the defect text.

20V-066Feb 6, 2020
Electrical System:Wiring

Honda (American Honda Motor Co.) is recalling certain 2018-2020 Odyssey vehicles. The wire harness for the third row seat accessory power outlet may get pinched between the unibody and rear trim panel, possibly damaging the wires and causing an electrical short.

Risk and remedy
Risk: An intermittent electrical short could overheat the wire harness, increasing the risk of a fire.
Remedy: Honda will notify owners, and dealers will inspect the third row seat accessory power outlet wire harness for damage, replacing it as necessary. If no damage is found, the dealer will apply protective tape and re-route the harness. All repairs will be performed free of charge. The recall began March 16, 2020. Owners may contact Honda customer service at 1-888-234-2138. Honda's number for this recall is T6U.

NHTSA investigations into the electrical system on the Odyssey

PE12-026opened Oct 2, 2012
Electrical · model years 2003 to 2004

Ignition interlock failure - rollaway. Closed jan 14, 2013, led to recall 12V-573.

NHTSA summary
On December 10, 2012, Honda Motor Company submitted a defect information report to NHTSA regarding ignition interlocks in approximately 576,117 model year MY) 2003 through 2004 Honda Pilot and Odyssey vehicles that are the subject of this investigation and 231,044 MY 2003 through 2006 Acura MDX vehicles (Recall No. 12V-573).Honda's report states that a design change to the ignition switch used in the recalled vehicles reduced the range of rotation for the ignition switch from 160 degrees in earlier designs to 125 degrees without a corresponding change to the ignition interlock blocking mechanism.The result was that excessive rotational force could damage a lever that would allow the driver to remove the ignition key that was in a position other than the Park position, which may allow the vehicle to roll away.ODI identified 176 complaints related to the alleged defect, including 48 roll away crashes.Threeof the incidents resulted in the following injuries to pedestrians:1) a broken foot and torn Achilles tendon; 2) a fractured fibula and crush injuries to a shin area; and 3) an incident requiring unspecified treatment at a hospital emergency room.This investigation is closed.The VOQs associated with this investigation are: 10486515, 10486393, 10486100, 10485010, 10482229, 10482091, 10481169, 10481105, 10481079, 10481027, 10480804, 10480648, 10480099, 10480009, 10479934, 10479695, 10479561, 10479517, 10479494, 10479484, 10479437, 10479421, 10479409, 10479343, 10478916, 10478876
EQ12-010opened Sep 28, 2012
Structure · model years 2005 to 2009

Stabilus rear liftgate struts failing. Closed dec 31, 2012.

NHTSA summary
Please see the attached closing resume summary.It has been attached to this document as a PDF.
EA08-015opened Aug 8, 2008
Structure · model years 2005

Unexpected closing of power liftgate. Closed apr 12, 2010, led to recall 10V-055.

NHTSA summary
Honda will replace the liftgate struts in approximately 21,776 model year 2005 Honda Odyssey Touring vehicles equipped with power liftgates that were built before a manufacturing change of the liftgate strut assembly on July 16, 2005 (NHTSA Recall No. 10V-055).Vehicles built after the change experience significantly lower failure rates.The recall will inform consumers of the dangers of the existing struts and provide the opportunity for vehicle owners to obtain new struts that are more robust.Based on Honda's action, the agency has decided to close the investigation.While Honda has not made a decision that the recalled vehicles contain a safety-related defect, in view of the recall, further use of the agency's resources does not appear to be warranted.The agency reserves the right to take further action if warranted by the circumstances.Additional information can be found in the attached Engineering Analysis Report.
PE08-026opened Apr 10, 2008
Structure · model years 2005

Unexpected closing of power liftgate. Closed aug 8, 2008.

NHTSA summary
THE LIFTGATE GAS STRUTS FOR THE SUBJECT VEHICLES MAY HAVE DAMAGED GAS SEALS THAT ALLOW THE LIFTGATE TO CLOSE UNEXPECTEDLY.AT THE COMPLETION OF A POWER-OPEN COMMAND, THE POWER LIFTGATE MAY EITHER CLOSE WITHOUT POWER ACTUATION (I.E., DESCEND UNASSISTED UNDER THE FORCE OF GRAVITY) OR AUTOMATICALLY POWER-CLOSE WITHOUT INPUT FROM THE OPERATOR.SOME OWNERS ARE CAUGHT UNAWARE OF THE UNINTENDED CLOSING OF THE LIFTGATE WHILE UNDER THE REAR LIFTGATE DOOR.THERE HAVE BEEN TEN REPORTED INJURIES RELATED TO THE ALLEGED PROBLEM ON THE SUBJECT VEHICLES.THIS INVESTIGATION HAS BEEN UPGRADED TO AN ENGINEERING ANALYSIS (EA08-015).
RQ00-014opened Jul 28, 2000
Structure · model years 1999 to 2000

Upexpected opening of sliding door. Closed apr 25, 2002, led to recall 99V-158.

NHTSA summary
There is no summary currently available

None of these investigations covers the 2018 model year.

What owners paid

8 of the 37 reports quote a price. Each dot is one quote. The middle half runs $691 to $1,600.

$691$1,000$1,600
$0k$2k$4k$6k$8k

When it happens

Too few of these reports state a mileage to give a range.

221
423
1424
1025
726

What owners wrote

“The Tailgate Control Module failed due to water getting in to it from normal rain. There seems to be a leak in the seam and caused the failure. I took it to the shop and confirmed the failure, purchased a new control module and replaced the faulty one. I opened up the faulty one and it had water damage inside.”

Filed Dec 19, 2025

“Crack in body seam above driver and passenger side of the tailgate AND underneath the roof rail cover caused water leakage. This resulted in a short of the power tailgate control module which draws down my battery and causes unexpected trunk closing during normal use. Family members have been hit in the head by the trunk due to the unexpected automatic emergency closing.”

Filed Jun 24, 2025

“The power tailgate opened by itself while I was driving on high way at around 60mph. Later it stopped working/won't open and the car battery died as well. Went to Honda dealership for a Diagnosis and found a water leakage on the roof of the back, causing the tailgate control module to be burned out by water damage.”

Filed Mar 16, 2025

“There is water leaking in the body which damages the power tailgate control module located at the rear driver side. the tailgate doesn’t open and endanger people inside in case there is any accident.”

Filed Feb 24, 2025

Should you keep driving it?

This page can't tell you that. 0 of 37 reports involved a crash and 2 people were hurt. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.

File your own report with NHTSA. Complaint counts are how a problem gets an investigation.

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