One problem related to wiring has been reported for the 2005 Saturn ION. The most recently reported issues are listed below.
: the contact stated while driving various speeds, the vehicle would not shift out of first gear. The service engine light illuminated and the vehicle stalled. It was started after one half hour and moved off the road. The vehicle was towed to the dealer twice where an undetermined part was replaced in the transmission and the ignition switch was also replaced. The problem reoccurred and the vehicle was driven to the dealer and the wring harness was replaced. The problem has not reoccurred.