P0705 - Transmission Range Sensor Circuit malfunction(PRNDL Input)
That's the neutral safety switch. It could be dirty, be out of adjustment, or a wire going to it could be corroded / cut / or have a loose terminal. There's usually some other symptom that accompanies that. There's an entire book on diagnosing transmission-related fault codes. They have pages of steps your mechanic will follow to find the cause.
Sunday, December 1st, 2013 AT 2:28 PM