K 3500 Truck 4WD V8-393 6.5L DSL Turbo (1993)
Input Speed Sensor Circuit
CIRCUIT DESCRIPTION
The input speed sensor is of the magnetic induction type. The sensor is located on the left side of the transmission just forward of center.
Serrations cut in the forward clutch housing induce a small AC current as they pass by the input speed sensor. While there is no specific diagnostic
trouble code for an input speed sensor fault, the PCM/TCM uses input speed sensor readings to calculate gear ratio, turbine speed, TCC slip, and
determine if the engine is operating.
TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks the input sensor circuit up to the PCM/TCM.
2. This test checks the input speed sensor output.
DIAGNOSTIC AIDS
Check all connectors and refer to "PCM/TCM Intermittent DTC(s) or Performance."
