* Steering column issue: The most likely culprit is a problem with the steering column lock mechanism itself. It might be jammed, worn out, or malfunctioning. This is a common problem in older vehicles.
* Shift linkage problem: Even though the shifter is in Park, the transmission might not *actually* be in Park. A problem with the shift linkage could be preventing the lock mechanism from engaging.
* Faulty ignition switch: The ignition switch itself might be failing, preventing the key from turning even though the transmission is in park.
* Key problem: While less likely if the key goes in, a damaged or worn key could be preventing it from fully engaging the ignition switch tumblers. Try a spare key if you have one.
* Low battery: A very weak battery can sometimes affect the electronic systems enough to interfere with the ignition.
* Security system: If your vehicle has a security system and it's malfunctioning, that could prevent the key from turning.
What to do:
1. Try jiggling the steering wheel: Gently try turning the steering wheel back and forth while turning the key. Sometimes a slight adjustment is all it needs.
2. Check the shifter: Make absolutely sure the shifter is firmly in Park. Try gently rocking the vehicle back and forth (with the parking brake firmly engaged). Sometimes this can help seat the transmission properly.
3. Try a spare key: If you have a spare key, try using that to see if the problem lies with the key itself.
4. Check the battery: If the battery is weak, it might affect the ignition system.
5. Professional help: If none of the above works, you'll likely need a professional mechanic to diagnose and repair the problem. This is likely a more involved repair, possibly requiring replacing parts in the steering column or ignition system.
Do not force the key. Forcing the key could cause further damage to the ignition switch or steering column. It's better to seek professional help if you're unable to solve the issue yourself.
