Eaton Gen 1 (AutoShift) Fault Code: 56 PID: PID 161 FMI: 2 Input Shaft Speed Sensor

Overview:
This code indicates an electrical problem in the input shaft speed sensor circuit. The signal from the sensor did not match the current operating conditions.

Detection:
A speed sensor is determined faulty when all the speed sensor readings are compared and one sensor is inconsistent.

Fallback:
This fault causes an In Place fallback. If the Input Shaft Speed Sensor fails before power-up, the transmission is unable to engage a gear and the fault code cannot be reproduced.

Required Tools:
1) Basic Hand Tools
2) Digital Volt/Ohm Meter
3) AutoSelect/AutoShift Troubleshooting Guide

Possible Causes:
1) Loose speed sensor
2) Contaminated sensor end
3) Damaged transmission harness
4) Malfunctioning input shaft speed sensor
5) Failed main drive gear
6) Malfunctioning transmission ECU

Categories DTC TRUCKS, Eaton, Gen 1 (AutoShift) Tags 1, 161, 2, 56, AutoShift, Code, Eaton, Fault, FMI, GEN, Input, PID, Sensor, Shaft, Speed

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