2021 Honda Odyssey electrical problems

ELECTRICAL SYSTEM

When coming to a complete atop, the engine switches off (the idle stop function), which is ok, but when I release the brake the engine often fails to restart. I’ve replaced the battery but this appears to be a common problem. It’s been happening more now at the end of summer when it’s hot for some reason. I was told there is a similar investigation open: EA25004

NHTSA complaint #11757074 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The contact owns a 2021 Honda Odyssey. The contact stated that while stopping at a red light, the vehicle idled and automatically turned off while stopped and then the vehicle restarted but the vehicle stalled. The electronics on the vehicle were not operating as designed. The contact attempted to restart the vehicle, but the vehicle failed to start. The contact's brother was able to jumpstart the vehicle, and the vehicle operated as needed. The dealer was contacted; however, the vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 72,000.

NHTSA complaint #11753593 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

2021 Odyssey EXL shuts off completely at a traffic stop light. Happened 2 times in a 2 week period. Without warning the engine switches off completely and puts itself in "P" mode, all light comes on as if in accessory mode, radio switches off, all doors unlocked. To get going, the driver had to press brake pedal and start the car again (via Engine Start /Stop button). This issue started in my car at 93K miles. Never had any issue with mine before that. But it is scary especially the engine switch off at stop lights and blocking traffic for a number of minutes before you know what happened and are able to restart the can. I have seen this issue reported a number of times on this site and it appears repetedly in web searches. Honda needs to identify the cause of this problem and issue a recall for it.

NHTSA complaint #11752152 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The infotainment screen randomly shuts off and displays the errors "Network communication lost" and "MOST Net Off". This has happened numerous times while in the middle of backing up and using the backup camera that normally displays on that screen. We took it to the dealership for repairs of the problem in 2025 and after changing a wiring harness, the screen itself, and then the harness again, they thought they had fixed it but the issue continued to happen and has increased in frequency since then. Honda has a recall that includes our model (NHTSA Recall No. : 23V-431) but we were apparently not included in it and their press release on it estimates 50% of vehicles of the year and model are affected. It's unclear what arbitrary data was used to determine effected vehicles but it's obvious by the amount of discourse about it online that it affects more than their initial estimate. Many people, like us, have tried to have it repaired at a dealership to no avail.

NHTSA complaint #11751816 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

COMPONENT/SYSTEM: The infotainment/audio head unit and instrument display, which communicate over the vehicle's MOST (Media Oriented Systems Transport) fiber-optic network via FAKRA connectors. The vehicle is available for inspection on request. FAILURE: While driving, the center display and Carplay screen spontaneously reboot and show "Network Communication Lost." During these events I intermittently lose the rearview backup camera and other display functions and navigation as well as communication. The failures are intermittent, happen more often over bumps, and sometimes at startup, and even during smooth road conditions. SAFETY RISK: Losing the rearview camera is a hazard when backing up, and having the instrument/infotainment display reboot while driving is distracting and removes information the driver relies on constantly. CONFIRMED BY A DEALER: Yes, repeatedly. The manufacturer issued a safety recall (Recall 23-047, "MOST FAKRA service cables"), which a franchised dealer performed in May 2024, replacing MOST network components. About 15 months later, the same defect returned; the dealer found the audio-unit connection was not secured, reseated it, and confirmed the wiring had proper continuity (ruling out rodent or wire damage). The dealer otherwise offered only workarounds - an aftermarket Bluetooth adapter and recording video of the failure - not a durable repair. The issue still persists. INSPECTED BY MANUFACTURER: The manufacturer-directed recall remedy was performed by the dealer; there has been no police or insurance inspection. WARNING MESSAGES: Yes - a "Network Communication Lost" message accompanies each reboot. The problem was present before and after the May 2024 recall and had clearly recurred by mid-2025. KEY POINT: This is a failed safety-recall remedy. Recall 23-047 was performed at about 29,000 miles and the same defect returned by about 36,700 miles - a failure within roughly 7,600 miles. It persists today.

NHTSA complaint #11750723 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

My 2021 Honda Odyssey Touring has experienced a severe engine stalling defect that creates an immediate traffic hazard. On multiple occasions during warm weather conditions, the Auto Idle-Stop system has engaged at a stoplight, but the vehicle completely failed to restart automatically when pressing the accelerator. Instead, the engine completely stalled out mid-drive, leaving the vehicle stranded in active traffic and requiring a manual cycle of the ignition button to turn back over. There were no dashboard warning lamps, error messages, or check engine lights prior to the engine stalling. The vehicle was taken to an authorized dealership (Honda of Middleburg Heights) for an emergency safety evaluation. The certified technician physically tested the starting system and explicitly confirmed the physical hardware failure on the invoice, stating: "The starter motor can be heard cranking slower than usual during start up. Recommend replacing the starter motor and relays." Despite this official mechanical diagnosis of a failing starter component causing an immediate traffic stall, regional management issued a flat refusal of coverage because my specific VIN was omitted from the automated database recall screens for Service Bulletins A23-008 and A23-010. I am filing this complaint to ensure federal investigators document this rigid VIN exclusion loop under the active NHTSA Engineering Analysis EA25004.

NHTSA complaint #11750213 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

In mid-March 2026, the power tailgate on my [year] Honda Odyssey lost power entirely. It does not respond to the key fob, the tailgate button, or the dashboard button — it will not open or close by any control. I personally inspected the tailgate area and found corrosion and rust present, consistent with prior water intrusion. I have since learned that this is a widely reported issue among 2018–2021 Honda Odyssey owners, and that a class action lawsuit ([XXX] v. American Honda Motor Co., Inc., filed in the U.S. District Court for the Central District of California) alleges a defect in rear body seam seals that lets water leak into the power tailgate control module, causing it to fail. The symptoms and physical evidence I found match those described by other owners and in the litigation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11747727 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

When stopping at an intersection the engine fails to restart after stopping due to the auto start/stop feature. The car tries to start and stalls and dies, and must be completely turned off before it will restart. This has happened 5-6 times now. There are no warning lights on the dash.

NHTSA complaint #11747208 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

What component or system failed or malfunctioned, and is it available for inspection upon request? The Auto Start/Stop function only works intermittently on our 2021 Honda Odyssey. Occasionally, when the Auto Start/Stop function does shut off the engine when the vehicle is at a complete stop, the engine fails to restart on its own. The vehicle is available for inspection upon request. How was your safety or the safety of others put at risk? This malfunction occurs intermittently and without warning when the vehicle is at a complete stop in traffic. The vehicle cannot be driven under its own power in this condition, often leaving it disabled in a traffic lane with other vehicles stuck behind and/or passing by at normal travel speeds. As such, it endangers both the occupants of my vehicle and the other vehicles in the vicinity. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. My local Honda dealership acknowledged the problem and completed a PGM-FI software update. However, this update did not correct the issue, and Honda refuses to take financial responsibility for the repairs necessary to correct the problem. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes. The following timeline details my interactions with my local Honda dealership regarding this issue: 4/13/23 - The dealership inspected the vehicle and claimed the Auto Start/Stop system was "operating as designed"; 9/6/24 - The dealership completed a PGM-FI update as directed by a Honda product update campaign; 2/12/26 - The dealership inspected the vehicle, suggested battery replacement (which tested good on 3/3/26), and if still not corrected, advised replacement of the starter at my expense. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? The problem has occurred without notice since purchase on 3/11/21.

NHTSA complaint #11742470 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

System crackles through the speakers and infotainment system shuts down completely. It may or may not reboot.. Most recently the screen was completely unresponsive, the radio would not turn off manually, and it did not turn off when the car turned off and the door was opened. Occurrence is random. The system may work fine for a few months and then crash multiple times daily and then go back to working normal again for a few months.

NHTSA complaint #11738180 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

Leaking from the roof and tail gate caused the electronic control modules in the sliding door and rear gate to fail.

NHTSA complaint #11730667 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The rearview camera that does not display an image which can reduce the driver's rear view, increasing the risk of a crash or injury. I had the vehicle inspected by a third party which believes this could be from insufficient repairs as part of the prior recall NHTSA ID Number: 23V431000 related to this same issue. Honda's recall service center's only solution is that I take the vehicle to a Honda dealership for inspection, at my expense, and that they will reimburse me if they determine it is related to this recall. The issue with the display not working has been going on for several weeks. The display will work temporarily when the battery is reset, the fuse is reset, or when the display itself was removed/replaced by the party I had inspect the unit.

NHTSA complaint #11721957 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The error message “Power Tailgate Problem” appeared on the dash. Following the error message, the power tailgate stopped working. It would not open or close with the remote, the button on the dash, or the button on the tailgate itself. I discovered water had been leaking in the tailgate and the trunk area of my vehicle as well as the back seat that was folded down in storage had gotten soaked. I took my van to the service center and they told me it was the seal above the door and that the leak had ruined the power module controlling the door. They repaired the issues. That was in April 2025. The same thing happened last week (January 2026). After looking into the error message and the tailgate problem, I’m finding that the door may open or close at any time on its own. The water in the electrical module may also start a fire. I have two small children and this van is our primary vehicle. I’ve reached out to the dealership from which I purchased the van, I reached out to a local Honda dealer and I contacted Honda customer service and no one is willing to fix this issue. I will be required to pay out of pocket again. I’m requesting a recall on this defect in design.

NHTSA complaint #11712381 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

the trunk door stopped working due to a leak from the rear left window seal causing the computer to become waterlogged the mechanic that fixed it said its a common issue with the Honda odyssey and should be recalled by Honda, I am therefore requesting the nhtsa to investigate this matter further so Honda should reimburse for the cost of the repair this issue can be a safety hazard in the event of a emergency egress from the trunk as it's not possible to open from the exterior and there was no prior warnings lamps or messages

NHTSA complaint #11711166 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

Power tailgate stopped working. Warning indicator indicated Power Tailgate failure. Dealer found water to be leaking onto tailgate unit from driver’s side roof rail. Recommended replacing and programming new PTG unit and resealing water leak. Repair cost was $1,311.51

NHTSA complaint #11711000 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

My rear hatch for the trunk was filling up with water every time it rained. Took it in to be looked at and they found the door wasn’t sealed during manufacturing and they sealed it. The water damage was already done and buttons for all things no longer lifts or opens the trunk door. My dash displays “ power tailgate problem” and nothing works to open it. I have to do it manually and I’m afraid it will cause further problems to the door.

NHTSA complaint #11709146 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The main screen went black for 3 mins while driving. Booted halfway back up then crashed again. Booted up again and then worked. Its done this 3 times and I've had van for 6 days. 32k miles one owner. Mint looking

NHTSA complaint #11701493 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

I hear a popping/crackling noise from the speakers then I get complete network loss for my backup camera, my dvd player, my clock, maps etc.System does a report after 5+ minutes. Message displayed before everything goes black is Network Connection Lost and MOST Net Off. This issue is ongoing and seems to happen now every day sometimes multiple times in a driving session. It just started about 2 weeks ago. There is an active recall for this exact issue for 2021 Honda Odysseys but my VIN does not seem to be included.

NHTSA complaint #11689851 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

Vehicle lost power resulting in the vehicle automatically going into park and powering off while driving. This has happened multiple times. In addition, we will get strange electronic codes. Tested battery and systems successfully, but problem persists.

NHTSA complaint #11689213 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

Can has been making a popping noise that can be felt in the steering wheel for 2 years. Honda has told me nothing was wrong after taking it in 4 times. Now my car keeps stalling at lights, sometimes it takes a while to get it to restart, and they can not figure out why. They keep saying the battery is fine and diagnostics finds nothing.

NHTSA complaint #11683344 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

Vehicle applied brakes for no reason. Lost ability to see reverse camera during backing up. Half of the instrument cluster went dim to become barely visible. Radio screen freezes randomly. Engine cuts out or shudders intermittently.

NHTSA complaint #11682827 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM:STARTER ASSEMBLY

The contact owns a 2021 Honda Odyssey. The contact stated that while attempting to start the vehicle, the engine failed to crank. There were no warning lights illuminated. The vehicle was towed to a local dealer, where it was diagnosed, and the contact was informed that the starter was faulty and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 66,000.

NHTSA complaint #11679974 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The vehicle's Auto Idle Stop (AIS) malfunctioned. The vehicle stalled and required a complete "shut down" to restart. The vehicle was first in line at a traffic light. The AIS system engaged. When I took my foot off the break to "go" when the light turned green, the car stalled. An error message popped up, indicating that I needed to shift the car into "park". I did so and the car did not start. I attempted to turn the car off several times, while in park and my foot depressing the break pedal. The car would not turn off. After three minutes of attempting to turn off the car and waiting, I was finally able to successfully start the car. I was traveling with my four young children, three of them in child car seats. I was nearly rear ended by one vehicle, despite having my hazard flashers on, because my car stalled at a traffic light when it was green. Two cars drove around me who were also stopped behind me at the traffic light. Another car came up to the traffic light and my vehicle and nearly rear ended me with my four young children in the car. This is the third time that this exact issue has occurred in my car. I brought it to my local Honda dealership on the same day that the issue first occurred. They inspected it but were unable to replicate it. They said they would make note of it but had not heard of such an issue. I had no idea this could be reported on this website. I was never told about this otherwise I would have reported this on the day that each of the two previous incidents occurred. This issue originally occurred the first time approximately 10/2022 and again for the second time approximately 4/2023. It just occurred for the third time today, 7/14/0225.

NHTSA complaint #11673383 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

2021 Odyssey EXL the Electric parking brake 'issue' warning comes on while driving and collision mitigation warning / lane assist switches off and flashes in console; when this happens the car continues to run but the dashboard warning lights comes up for Parking brake / Collision Warning and or Lane assist. It gets cleared after I turn on/off the car couple of times and drive for approximately 5 miles. Those features had to be turned on manually, once the car is in parked mode, again. The issue started in the car at around 48K miles. Never had any issue with it before that.

NHTSA complaint #11670202 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

2021 Odyssey EXL shuts off completely in traffic stop and go conditions. Happened three times in a 2 week period. Twice in city roads at traffic stop light and once in highway when the cars are in stop / go mode due to heavy traffic. Engine switches off completely and puts itself in "P" mode, all light comes on as if in accessory mode, radio switches off, all doors unlocked. To get going, the driver had to press brake pedal and start the car again (via Engine Start /Stop button). This issue started in the car at 43K miles. Never had any issue with mine before that. But it is scary especially the engine switch off in highway and traffic stop light.

NHTSA complaint #11670208 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The contact owns a 2021 Honda Odyssey. The contact stated while at a stop light and depressing the brake pedal, the engine turned off; however, once the accelerator pedal was depressed, the Auto START/STOP failed to operate as intended. The contact turned off and restarted the vehicle and the vehicle started to work as intended. No warning light was illuminated. The vehicle was not taken to a dealer or independent mechanic to be diagnosed. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 32,000.

NHTSA complaint #11660379 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

After my van sit at home all day while it was raining. I went out side to put something in the back of the van and the tail gate wouldn't open had warning symbol on the dash board. I only have 61,729 miles on my van and no accidents

NHTSA complaint #11660556 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

Tailgate would not work (electronically or manually) Other Odyssey owners have had similar problems, some included tailgate opening on its own There were no problems until it just wouldn’t open one day Dealer replaced module for $700+

NHTSA complaint #11655676 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

It started that all the sensor in our car started to go off. We were told we had a bad battery, even thought we had replaced it new just last year. Once we had the battery checked and alternator. The sensors started to act up again, out tail gate started to malfunction. Wouldn’t automatically close. A few weeks ago driving down the road the tail gate opened and the anti theft system started going off while the car was running and still going. Come to find out there is a water leak in the rear that has gotten into the rear fuse box and has cause substantial corrosion. The latch to the tail gate is broken. Honda is telling us our extended warranty doesn’t cover any of this, even though it is common knowledge, that the water leak is a known problem from 2018-2021. We just found out a few days ago.

NHTSA complaint #11652678 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

Auto Idle Stop not restarting after shutting the engine down.

NHTSA complaint #11651667 — an unverified report by a vehicle owner.