No Range Shift Checks

If the vehicle will not shift into 4L, check the speed sensor brake switch input transmission interlocks (neutral or clutch in), clutch pedal position (CCP) sensor, and digital transmission range (DTR) sensor. For diagnosis and testing of the DTR sensor. Also check the 4L switch (C3) to see if the module is getting a signal. Check for corroded connections.

If the vehicle won't shift back to 4H, follow the proper sequence of being stopped and having the vehicle in neutral (or clutch in) when pushing the switch. Check the 4L switch and the motor position sensor.