NHTSA complaint #11711699

Owner complaint summary

The windshield wiper switch assembly (column stalk/switch) malfunctions intermittently, sending unintended signals that activate the wipers despite the stalk being firmly in the OFF position. The component is still installed in the vehicle and is available for inspection upon request. Suspected part numbers include 84652-06400 or similar variants. How was your safety or the safety of others put at risk? Sudden, unexpected wiper activation (typically 1-2 wipes, occasionally more) while driving creates a serious distraction and safety hazard. It can startle the driver, cause momentary loss of vehicle control or focus (especially at highway speeds or in traffic), and briefly obstruct vision. This risk is heightened during rain, when wipers are needed but behave erratically, or during acceleration/turns where vibration triggers it—potentially leading to accidents. Has the problem been reproduced or confirmed by a dealer or independent service center? No, the Toyota dealership has not reproduced or confirmed it during short test drives, as the issue is highly intermittent and occurs mainly after warmup from extended driving (20+ minutes), on hot days or after parking off for ~1 hour in heat/vibration. Similar cases reported by other 2020 Corolla owners on Reddit (r/COROLLA) and Toyota Nation forums were eventually diagnosed and fixed by replacing the wiper switch due to worn internal contacts/PCB from heat/vibration. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? The vehicle was brought to a Toyota dealership, but no detailed inspection or repair occurred due to lack of replication. No inspections by police, insurance, Toyota corporate (manufacturer), or others have taken place. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No warning lamps, messages, dashboard indicators, or prior symptoms