Security light flashing car starts runs for two seconds then shuts off?

WILLIE HURLOCKER

MEMBER
2005 DODGE MAGNUM
5.7L
V8
2WD
AUTOMATIC
144,000 MILES

I got an ignition switch from the junk yard, same year same model, same motor. Unplugged negative cable. Took my switch out. Took my cylinder out swapped it. Put it all back together. Car starts but shuts off every time after 2 seconds, security light flashing. When I take the key cylinder out and put mine in, shouldn't it read it or do I need to take and swap the other sensors on the ignition and just use the ignition switch from the new one? Thanks guys

1 Reply

STEVE W.

MECHANIC
13,014 POSTS

The system isn't recognizing the key in the new switch, keys have to be programmed into the cars SKREEM for them to work. That prevents swaps like you tried from defeating the anti-theft system. Also, the SKREEM in that year doesn't allow you to use a key that has already been programmed into another vehicle so a used key from another car also won't work and cannot be programmed to work. They used a different system on those, the key code gets read by the car, but the key won't send that code unless the key recognizes the car's code first.
Basically, you have three options on those. You go to the dealer who orders you for a new switch with new keys, then you install it and use a scan tool to erase the old keys and enter the new ones. This method also means that the key will not work in the trunk or doors so you either carry 2 keys or replace all the locks. The second method is to install the used lock as is and have a mobile locksmith come out and cut 2 new keys to fit that cylinder and program those in, you still cannot open the doors. The third option is a combination, you take the used cylinder and your original to a smith and have them re-pin the cylinder to use your old keys and make you new keys. Then in theory you install the cylinder and use your old key to start it and drive back to the lock shop to have them erase all the keys and program in the new keys and the working old one.
There is no method to program in keys as a DIY, you have to have the scan tool.
This is the operation for replacing keys out of service information.

Each ignition key transponder also has a unique ID code that is assigned at the time the key is manufactured. When a key is programmed into the SKREEM/WCM, the transponder ID code is learned by the module and the transponder acquires the unique Secret Key ID code from the SKREEM/WCM. To program ignition keys into the SKREEM/WCM, follow the programming steps outlined in the diagnostic scan tool for "Program Ignition Keys or Key FOBs" under "Miscellaneous Functions" for the "WCM/Wireless Control Module" menu item.

NOTE - A maximum of eight keys can be learned to each SKREEM. Once a key is learned to a SKREEM, that key has acquired the Secret Key for that SKREEM and cannot be transferred to any other SKREEM or vehicle.

If ignition key programming is unsuccessful, the scan tool will display one of the following error messages-
Programming Not Attempted - The scan tool attempts to read the programmed key status and there are no keys programmed into SKREEM memory.
Programming Key Failed (Possible Used Key From Wrong Vehicle) - SKREEM is unable to program an ignition key transponder due to one of the following:
- The ignition key transponder is faulty.
- The ignition key transponder is or has been already programmed to another vehicle.

8 Keys Already Learned, Programming Not Done - The SKREEM transponder ID memory is full.
Learned Key In Ignition - The ID for the ignition key transponder currently in the ignition lock cylinder is already programmed into SKREEM memory.