Battery back-up sounder
Can you tell me how the battery back-up sounder under the radiator expansion tank on my 2004 Rover 45 works and what it is for? I cannot find any information on it. Michael Kent The battery back-up unit (part no YWK000041) that’s located under the coolant expansion tank is for the vehicle alarm system. It contains its own battery unit, which should sound the alarm when required even if the vehicle’s battery is either flat or disconnected. Unfortunately, the unit is no longer available from Rover parts suppliers, but some owners have managed to replace the internal battery if required.