Code 74, Transmission Input Speed Error 4L80-E Transmission: Notes

1995 Chevrolet Forward Control 7.4 NSECTION Notes

Sensor is a permanent magnet type. When rotating trigger teeth pass sensor, an AC voltage signal is produced. Signal voltage and frequency varies with forward rotational speed.

NOTE: Test numbers refer to numbers on diagnostic chart.
  1. Checks entire circuit for continuity.
  2. Checks output of input speed sensor.
RENDER: 1.0x

NO RELATED

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

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