Complaints fall by two-thirds to 130 — the story now is water getting into the electronics, not anything under the hood.

Auto idle-stop switches the engine off when you stop and restarts it when you lift off the brake. On the 2021, owners report the restart failing: the engine dies at a junction and will not come back, sometimes for long enough to be genuinely dangerous. One describes the van shutting off completely at a traffic light twice in two weeks with no warning; another says 'the car tries to start and stalls'; another reports a severe stalling defect that creates an immediate traffic hazard. Owners' habit is to switch idle-stop off every time they start the van, since it turns itself back on. Honda has acknowledged a no-restart condition on later Odysseys — it asked dealers to inspect and collect parts from 2023 to 2025 vans with 'a no auto re-start condition after going into an auto idle stop' — but that is an open investigation naming other years, not a programme covering this one, and there is no recall for it on the 2021. Sit through a dozen stop-and-go cycles on the test drive with idle-stop left on.

The 2021 escapes the sliding-door recalls that cover 2018 to 2020, but the doors are still worth a hard look. One owner reports both door latches failing, the first at three years and the second at five, leaving a door that will not close fully. Others describe the doors becoming unreliable after water reached their control modules. Honda's own technical bulletin for 2018 to 2022 vans also admits an unresolved problem with the sliding-door windows: they stop partway and roll back down when you use one-touch Auto-Up, because of a software mismatch between the switch and the window regulator, and Honda's guidance to dealers says 'there is currently no recommended repair'. A mechanic who works on these doors traces a separate common complaint — the door closing then re-opening by itself — not to the motor but to the pinch-protection sensor strip in the door's leading edge, which he says Honda did not seal properly, so water gets in and the wet sensor reports an obstruction that isn't there. He disconnects the sensor and reckons it saves around $2,000 against replacing the motor. Be careful with that: disconnecting it removes the protection that stops the door on a child's hand, and he says as much on camera.

The 2021's eight campaigns are all free. Two are airbag campaigns describing opposite failures: 26V-227 covers software that can deploy the side and curtain airbags unexpectedly, and 24V-064, later expanded by 26V-332, covers a front-passenger seat-weight sensor that can crack and short so an airbag deploys when it shouldn't. Recall 23V-174 covers side-view mirror heating pads that weren't bonded properly, so the mirror glass can detach; dealers replace both mirrors free. Recall 23V-431 replaces a faulty connector on the MOST network — the fibre-optic link between the audio and display systems — that can leave the rearview camera blank; owners of this year report exactly the matching symptom, the system crackling through the speakers and the infotainment screen shutting down and refusing to reboot. Recall 23V-858 is the large in-tank fuel-pump campaign that can otherwise stall the engine. Two further campaigns apply only to converted vans: 21V-010 covers Braun Corporation wheelchair conversions with a fuel tank that can overfill into the charcoal canister, and 25V-877 covers Vantage Mobility wheelchair restraints whose retractors may not lock. Neither can apply to a standard van.

One owner reports a rear passenger-side shock absorber snapping on a family road trip, with the van fishtailing over every bump afterwards — a single report rather than a pattern, but the closely related 2020 and 2022 both show rear coil springs breaking, so the rear suspension is worth a torch and a bounce test. Set against that, here is what has genuinely dropped off this year's list: the connecting-rod-bearing recall that could destroy the engine ends at 2019, as does the timing-belt recall and the sliding-door latch recall where a door could open while driving. The nine-speed transmission of the launch years has been replaced by a ten-speed, and a dealership technician who services these vans reports few failures on either. The 2021's problems are things that leak, stall or fail to restart — annoying and occasionally unsafe, but not engine-out money.