Chrysler vehicles 2018- now require the 12+8 cable to clear DTCs and to add keys. Here we successfully added a new key fob with Autel IM508 XP400 and autel 12+8 cable for Dodge RAM 3500 year 2018 with secure gateway module (SGM). Program key in auto mode.
We’ve got that connected right there behind the stereo
Turn the ignition off and turn on the emergency flashers
Read security password
Select Keyless System (CAN) – Key Learning – Key Learning
Turn the ignition off and turn on the emergency flashers
Put smart be to be learned in vehicle and take other keys out of the vehicle
Auto fill-in 4-digit pin to access
Press LOCK or UNLOCK button on the remote control
Key learning successful
Put everything back
And test remote control and new key.
Done.
http://blog.obdii365.com/2021/09/08/autel-im508-program-2018-dodge-ram-3500-key-fob/