Honda Odyssey keyless entry and auto start malfunction after alternator replacement on Honda Odyssey

Some Honda Odyssey owners report experiencing keyless entry and auto start malfunctions following an alternator replacement. These issues may stem from the alternator affecting the keyless entry computer board, potentially leading to corrosion and a short that keeps the ignition in the "run" position. Additionally, problems with the Start/Stop button and keyless start system could be linked to the key fob or the need for cleaning and sealing of the affected board area. Other contributing factors might include battery, alternator, or starter issues. If the key fob fails, it could be due to a dead battery, water damage, or fob failure, with signs of a weakening battery often appearing prior to complete failure. To resolve these malfunctions, owners are advised to clean and seal the affected area, check the key fob battery, and inspect the battery, alternator, and starter.