T190 Lights on but no one home.

[BackBlade78]

Hi, hopefully someone can help with this error. In the middle of normal activity I had my 2012 T190 shut down unexpectedly and it displayed error M7748 (Key Switch Multiple). All the lights on the display are on EVEN WITH THE KEY IN THE OFF POSITION. I tried disconnecting the battery and letting it rest which did not work, then I unplugged all the main wiring harnesses to check their condition and they were all perfect and then finally I disconnected the keyed ignition and the display turned off. I then plugged the ignition back in, turned the key and it cranked and started. I though great, it's a faulty ignition switch so ordered a new one.
Today I went to install the new switch however the problem didn't go away. With the new (or old) ignition switch plugged in in the off position, as soon as I connect the battery the display lights up, then beeps and displays M7748. Nothing happens when I turn the key to start it.
Things I have tried:
hot wiring from the starter motor
replacing all the replays
replacing all the fuses
checked the square main harness connection between the body and the cabin
checked all connections behind the display and ignition
checked the 100A fuse
checked there is power at the ignition
checked the connections near the battery (3 x plugs)
cleaned the terminals and the contact going to the starter
and finally... walked away defeated

Any leads or ideas would be greatly appreciated! Thanks

 

[BackBlade78]

So after a bit of google searching I came across this thread:

s205 code 77-48

was running fine shut off to get drink of water heavy rain came in then wouldn't crank getting code 77-48 what do i do to fix problem

www.skidsteerforum.com

I disconnected the battery, unplugged the ACD connector above the battery, reconnected the battery and she started!

 

[mrbb]

glad you got your solution, I know how frustrating things can be when they should work but don't
and I am also glad you posted your findings , as when folks tell rte whole story start to finish /fix, its more likely to help others!