Wireless reverse camera from Maplin

Okay since my wife Lynne has a nice new Kuga and it has blacked out windows, and the reverse lights are poor at best when trying to reverse at night through this glass, I thought Id buy her a colour wireless camera as advertised from Maplin as not only was it wireless but it was IR illuminated and excellent at night, wel it took me 4 hours to fit the item and to hide the monitor away from view from prospective car thieves I decided to position it on the Velcro strips behind the sun visor, all was going well till she took the car away to see her doctor and phoned me to say that the car said it was not able to see the Key Fob inside the car, so the engine wouldn't start, I jumped in my car and drove down to meet her with the second spare key Fob .... It too didn't work ..... My old boss came to mind and his voice resounded through my head " If something doesn't work after you've been working on a problem check your work before perusing another fault course" I disconnected the monitor from the power ( the camera and the wireless thingy was still powered when in reverse, so it was only the monitor that wouldn't work now) She pressed the button and the engine started we connected the power and the same fault with no Key Fob Found was shown..... Embarrassed I removed the camera kit and took it back to Maplin.... Got a credit note ... So let this be a warning with Wireless Technology in new cars and thinking that we ca still modify anything without any consequences ....
Rod