What's with the key

Rickshaw · 2nd October 2021, 11:20

My Tourer passed MOT about a month ago and shortly after refused to start. Jump start from another car failed . RAC diagnosed faulty / dead battery - was from 2014 so lasted well. Installed a new battery , all lights , horn , radio etc work BUT starter motor would not work - not any sound at all. At this point I began to think of possible causes eg
• failed ignition switch – but most devices working
• a fuse – have yet to check this but now not likely ( see below)
I then thought outside the box and wondered whether my ‘key’ status was to blame. You see , the fob fell apart a short while ago ( as they do ). I have some spare fob shells and moved all the electronics across into a new one BUT simply could not free up the metal key shaft. Solution – I left the metal shaft in the dead old shell and kept the electronics in the new shell with both on the same key ring. New fob electronics work eg open car, lock etc and old metal shaft will unlock drivers door. In either case all devices , horn , radio, lights work. BUT nothing from starter motor. At this point I decided to try my spare key - it worked !! So it would seem both metal shaft and electronics have to be housed in same shell – but I am not aware of any electrical connection to the shaft and cannot understand why the shaft alone cannot start the car even when fob has opened car? Can anyone explain this to me ? Observations welcome.

2nd October 2021, 11:20	#1
Rickshaw Loves to post Rover 75 Tourer, 2 X75 Saloon , MGTF Sunstorm Join Date: Jan 2013 Location: Guildford Posts: 380 Thanks: 497 Thanked 172 Times in 93 Posts	What's with the key My Tourer passed MOT about a month ago and shortly after refused to start. Jump start from another car failed . RAC diagnosed faulty / dead battery - was from 2014 so lasted well. Installed a new battery , all lights , horn , radio etc work BUT starter motor would not work - not any sound at all. At this point I began to think of possible causes eg • failed ignition switch – but most devices working • a fuse – have yet to check this but now not likely ( see below) I then thought outside the box and wondered whether my ‘key’ status was to blame. You see , the fob fell apart a short while ago ( as they do ). I have some spare fob shells and moved all the electronics across into a new one BUT simply could not free up the metal key shaft. Solution – I left the metal shaft in the dead old shell and kept the electronics in the new shell with both on the same key ring. New fob electronics work eg open car, lock etc and old metal shaft will unlock drivers door. In either case all devices , horn , radio, lights work. BUT nothing from starter motor. At this point I decided to try my spare key - it worked !! So it would seem both metal shaft and electronics have to be housed in same shell – but I am not aware of any electrical connection to the shaft and cannot understand why the shaft alone cannot start the car even when fob has opened car? Can anyone explain this to me ? Observations welcome.