Input Speed Sensor Circuit Check: Notes

1992 GMC Magnavan 5.7 KSECTION Notes

The input sensor is of the magnetic induction type and is located on the left side of the transmission, forward of center. Serrations in the forward clutch housing induce a small A/C current as they pass by the input sensor. While there is no specific code for an input sensor problem, the PCM/TCM uses input sensor readings to calculate gear ratio, turbine speed, TCC slip, and determine if the engine is running.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. This test checks the input sensor circuit up to the PCM/TCM.
  2. This test checks the sensor output.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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