Adaptive Cruise Control problems of the 2024 Honda Accord

Component/system: collision mitigation braking system (cmbs) or related software. Vehicle available for inspection. Safety risk: vehicle brakes or decelerates unexpectedly during normal driving, risking rear-end collisions. Most recent incident on August 23, 2025, required override by pressing accelerator and shifting to neutral in traffic. Reproduction: dealer could not replicate issue during may 16, 2025 visit. No diagnostic codes found. Radar and braking systems reported as “operating normally. ” a second evaluation occurred after September 5, 2025, with no resolution; issue persists. Inspection: inspected by Honda dealership twice—on may 16, 2025 (invoice #488382) and again after September 5, 2025. No third-party inspections. Symptoms: braking occurs in sport, normal, and econ modes. Happens when accelerating from stop or easing off accelerator. Brake light activates falsely. No warning lamps or messages prior to failure. Issue has occurred 10+ times over the past year. Related software issues: radio failure (resolved via software update). Clock shows incorrect time. Apple carplay fails to connect until restart. Navigation compass shows concentric circles.

My car started shaking like it didn’t want to go. My engine light came on. Then it showed road departure mitigation system problem, collision mitigation system problem, adaptive. Those control problem, and emissions system problem then says engine is not functioning properly.

I was driving on a highway when the engine light came on and the car immediately started slowing down even though I was pressing the gas pedal. It flashed there was a failure of the brake system, collision mitigation braking system, road departure mitigation system, hill start assist system, and adaptive cruise control system. The check battery light also came on. The car decelerated on its own with brakes engaged. I had to choice but to immediately pull over and luckily was able to steer to an off ramp and into a parking lot.

Driving at highway speed with cruise control active, cruise turns off and car immediately feels like manual steering and accelerator harder to push. Warning lights displayed adaptive cruise, lane departure and brake system, see dealer. Exited the highway and restarted the car. Lights went off. Taking to dealer via appointment. Dealer says they can't determine whether or not there could be danger of driving the vehicle and can't get the car in for more than a week, leaving me without transportation should something go wrong.

2023 and 2024 hybrid Accord vehicles liberally activate brake lights while cruise control is active under even the slightest level of deceleration creating an appearance of a “brake check” when there is no brake check. A traditional car’s cruise control, for instance when set to 60mph allows you to depress the accelerator, speed up to 65mph to pass a vehicle, and then release the accelerator. The car then slows down naturally and begins controlling at 60mph. The deceleration is gentle and the brakes are not applied and the brake lights do not illuminate. The Accord hybrid under the same conditions will apply some level of regeneration to slow the vehicle and also activate the brake light to vehicles behind. While it’s understandable that the brake light would be illuminated if substantial regeneration is being applied, the brake light illuminates under even the slightest deceleration creating an unnecessary hazard. This can occur if the car is slowing down from only 2mph above the set point. Brake lights illuminate although the amount of regeneration being applied is negligible. It can also happen coming over the crest of a hill on a gentle downslope even with no prior depression of the accelerator. This is a serious deficiency and incorrect behavior. The brake lights should only illuminate under substantial regeneration or application of the brake pedal.