Where is the back up alarm relay in a Ford E-350?

In a Ford E-350, the backup alarm relay is typically located in the fuse box under the dashboard or in the engine compartment. You can find it by consulting the vehicle’s owner’s manual, which provides a diagram of the fuse box and the specific location of the backup alarm relay. If you're unable to locate it, checking for a relay labeled specifically for the backup alarm or reverse lights might help.