Same Problem-My 2006 GX470 won't start -Key won't turn.

When this happens to me ... I will wiggle/turn the steering wheel while trying to turn the ignition key ... and often, the steering wheel will unlock when you're able to turn the key

Yes, a valet key should start the car but won't open glove box or trunk.

Duplicated question

on a lot of these late model computer base cars when battery power get low the computer gets confused. try this disconnect the neg. battery cable. charge the battery. reconnect and try again. my son cobalt battery went bad key was stuck in the igntion. good luck.

Make sure your steering wheel isn't locked. Sometimes a key won't turn until you jiggle the wheel while trying to turn the key.

Close the doors. Lock the doors using the buttons on the key fob. Use the fob to again unlock the doors. The key should then work the ignition. If this will not work, you will have to tow your vehicle to the dealer and buy a new key and/or fob and have it programmed to the vehicle.

Ignition - Key Stuck In Ignition Switch/Won't Turn Bulletin No.: 06-02-35-005 Date: February 28, 2006 TECHNICAL Subject: Key Stuck in Ignition, Key Will Not Return to Off Position, Shifter Button Won't Release in Park Position (Adjust Shifter Detent Finger) Models: 2002-2005 Chevrolet Monte Carlo Condition Customers may comment on any of the following conditions: - The key is stuck in the ignition cylinder. - They cannot return the key to the off position to remove the key. - The shifter button won't release in the park position. Cause This condition may be caused by the detent finger shifting over time. This may result in mis-alignment and binding of the shift rod on the shift position guide.
WHERE YOUR SHIFTER IS YOU WILL HAVE TO TAKE IT APART ..MAYBE THE RUBBER BOOT IS IT THE WAY,OR THE SHIFT LOCK SELINOID WHENT BAD

MAKE SURE YOU USING THE RIGHT KEYS. TRY ANOTHER IGNITION KEY.PLACE KEY IN THE SWITCH. TURN IGNITION SWITCH TO ON POSITION UNTIL IMMOBILIZER WARNING LAMP ILLUMINATES FOR 2 TO 3 SECONDS. IF IMMOBILIZER WARNING LAMP ILLUMINATES FOR 2 TO 3 SECONDS THEN FLASHES RAPIDLY.KEY CODE NOT RECOGNIZED.REMOVE KEY AND TRY AGAIN. IF ALL FAILS TAKE CAR TO DEALERSHIP THEY HAVE TO USE DIAGNOSTIC EQUIPMENT TO FIX CAR.PROBLEM COULD BE IN THE IGNITION SWITCH,BCM,FAULT IN THE ECM OR IMMOBILIZER CODE INCORRECT.

FLAT KEYS OR NON CHIPPED DOOR KEYS AUDI CALLS THEM ARE NOT TO START THE VEHICLE THEY ARE ONLY TO OPEN THE DOOR IN CASE OF AN EMERGENCY

the tumblers inside the lock are jambed. you will need a new replacement lock cylinder