Output Speed Sensor Circuit Check (2WD) "C/K/G & P" Series: Notes

WARNING: This page does not describe the selected car, but rather 24 other vehicles, including the 1992 GMC Yukon, 1992 GMC Vandura Special, 1992 GMC Vandura, 1992 GMC Value Van, and 1992 GMC Suburban. However, it is still accessible from the selected car via links, so may be relevant.

The output sensor circuit consists of a magnetic induction-type sensor, digital ratio adapter, and wiring. Gear teeth pressed on the outside diameter of the output carrier assembly induce an alternating current in the sensor.

This current is transmitted to a digital ratio adapter, where it is passed on to the PCM/TCM. The digital ratio adapter compensates for various axle ratios, and converts the signal to a square wave for use by the speedometer, cruise control and anti-lock brake system. If the input sensor is not operational at start up, it can cause the output sensor to read zero.

NOTE: Test numbers refer to test numbers on diagnostic chart.

This test checks the speed signal on circuit No. 437 at the PCM/TCM from the digital ratio adapter.
This test checks for a speed signal from the output speed sensor to the digital ratio adapter.
This test checks the output speed sensor.