* Transmission Range Sensor (TRS) Problem: This sensor tells the transmission and the shifter what gear you're in. A faulty TRS is a common culprit; it might be sending an incorrect signal, leading to the lockout.
* Brake Pedal Switch Issue: The shifter is usually interlocked with the brake pedal. If the brake pedal switch is malfunctioning (either not making contact when the brake is pressed, or sticking), the system will prevent shifting. The car thinks the brake isn't engaged, thus locking the shifter.
* Shift Interlock Cable or Linkage Problem: The mechanical linkage between the shifter and the transmission could be broken, bent, or otherwise out of adjustment. This prevents the shifter from moving correctly.
* Low Transmission Fluid: While less likely to *directly* cause a lockout, extremely low transmission fluid can lead to problems that trigger the safety mechanism. Check your fluid level.
* Electrical Problem: A short circuit, blown fuse, or other electrical issue within the transmission or related control systems could be disrupting the normal function.
* Steering Wheel Lock: Although less probable in relation to the transmission *shift* being locked, a malfunctioning steering wheel lock could inadvertently contribute to a restricted gear shift.
What to do:
1. Check your brake lights: Do they work when you press the brake pedal? If not, the brake light switch is a likely suspect.
2. Check the transmission fluid: Make sure the level is correct and the fluid is clean.
3. Try gently rocking the vehicle: Sometimes, a slight rocking motion can free up a stuck linkage.
4. Check fuses: Consult your owner's manual to locate and check fuses related to the transmission and shift interlock system.
5. Have it professionally diagnosed: If none of the above solves the problem, you should take your Explorer to a mechanic. They have the tools and expertise to properly diagnose the issue and perform the necessary repairs. Trying to force the shifter could cause further damage.
