DTC 85

DTC 85:

VSS & Input/Output Speed Sensor Circuit (4WD):

CIRCUIT DESCRIPTION:
The PCM/TCM calculates the actual gear ratio from input and vehicle speed readings while in each gear and compares these to what the gear ratio should be considering the selected gear range. This monitor includes reverse but will not include overdrive.

TEST DESCRIPTION:
Number(s) below refer to circled number(s) on the diagnostic chart.

1. This test checks the proper function of the input speed sensor.

2. This test checks the correct functioning of the vehicle sensor.

DIAGNOSTIC AIDS:
The PCM/TCM uses the VSS buffer module to indicate what gear range has been selected. The VSS buffer module must be functioning properly or DTC 85 may set.
Check all connections at the transmission pass-thru connector. Refer to "INTERMITTENTS".

Gear Ratio Chart:

Compare scan tool gear ratio display to gear ratio chart.