2018 Honda Odyssey · symptom sheet

Battery dies or the car will not start

51owner reports
30,000median miles
$6,000median quote
0involved a crash

Newest report Aug 28, 2026 · checked Sep 9, 2026

256 of the 977 complaints on this car are about the electrical system. 51 of those describe dead battery.

Tick what matches of 51 reports

dead after sitting a day or two

needed a jump start

battery replaced more than once

warning lights or messages

the dealer found a drain

the dealer found nothing

What got replaced

Owners who name the part that was replaced mention the battery (48 reports), the module (9 reports) and the alternator (3 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

None of these investigations covers the 2018 model year.

What owners paid

5 of the 51 reports quote a price. Each dot is one quote. The middle half runs $1,600 to $7,000.

$1,600$6,000$7,000

$0k$2k$4k$6k$8k

When it happens

The middle half of failures fell between 10,077 and 40,000 miles, from the 17 reports that gave a mileage.

117

318

519

320

321

322

1323

624

725

726

What owners wrote

“Failure of the forward-looking multipurpose camera after a simple battery change. Many safety features are now inoperative including emergency braking, lane keeping assist, adaptive cruise control, among others. Ultimately, a routine maintenance item (battery replacement) is causing the failure of vehicle safety systems.”
Filed Jul 30, 2026

“Power Tailgate Failure/Dead Battery from Body Leak. currently power tailgate is not functioning.”
Filed Apr 1, 2026

“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

Should you keep driving it?

This page can't tell you that. 0 of 51 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.