Turbine speed sensor, voltage interference
Check that there is no damage or short circuit on the external cable harness. Contact an Allison dealer.
What you'll see
No driver-visible symptom recorded.
System reaction
The Allison fault code number is: P0716.The fault code is set if any of the following occur: Improbably large changes in turbine speed when the rotational speed is above 800 rpm for more than 0.15 seconds.Voltage interference from the sensor.The electrical cables to the sensor have been switched over, the requested gear is not neutral, next clutch control is completed and turbine speed is above 100 rpm.If the fault occurs when driving with the forward gear range selected and a gear-change has been carried out, the gearbox will maintain the current gear. If the fault occurs when driving with the forward gear range selected and gear changing is in progress, the gearbox will return to the previous gear after which the gearbox will carry out the requested gear-change. The lock-up cannot be locked. The control unit shuts off gear changing adaptation. The fault code can only be set on vehicles which have fire engine calibration in the control unit.The fault code is cleared automatically, when the vehicle has completed 40 start-up cycles without the fault being detected again.
Diagnostic depth
The control unit has detected interference in the voltage from the turbine speed sensor
A possible cause of the fault may be damage to the cable harness or a defective turbine speed sensor.