Test L: The Vehicle Does Not Shift Between 4H and 4L Modes Correctly

Pinpoint Test L: The Vehicle Does Not Shift Between 411 And 4L Modes Correctly Normal Operation

The high-low shift occurs when the reduction shift fork moves the high-low collar to lock the planetary gear set to the output shafi. The torque transmitted through the sun gear from the input shaft turns the front planetary gear set assembly. The front planetary gear set assembly now engaged provides transfer case speed reduction. Certain criteria such as vehicle speed and transmission range selection must be met before this shift can occur.

Possible Causes

Transmission neutral switch (or clutch pedal position [CPP] switch) hardwired to the 4X4 control module

Brake ON/OFF (BOO) switch hardwired to the 4X4 control module

ABS vehicle speed inputs hardwired to the 4X4 control module

PINPOINT TEST L: THE VEHICLE DOES NOT SHIFT BETWEEN H AND L MODES CORRECTLY

NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.