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Pinpoint Test R : The Hill Descent Control™ System Is Inoperative Or Cannot Be Disabled: Notes

WARNING: This page is about a different car, the 2018 Ford F-550 Super Duty, 2018 Ford F-450 Super Duty, 2018 Ford F-350 Super Duty, and 2018 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

Refer to Instrument Cluster for schematic and connector information.

Normal Operation and Fault Conditions 

The Hill Descent Control™ switch is used to activate and deactivate the Hill Descent Control™ system. When the driver presses the Hill Descent Control™ switch, the IPC receives a ground signal from the switch and illuminates the Hill Descent Control™ indicator. The IPC sends a Hill Descent Control™ switch message to the GWM over the HS-CAN3 and the GWM relays this message to the ABS module over the HS-CAN2. The ABS module takes the necessary action depending on the switch inputs and traction control message.

The Hill Descent Control™ switch is part of the hazard switch assembly.

DTC Fault Trigger Conditions 

DTC Description Fault Trigger Conditions
U0401:86 Invalid Data Received From ECM/PCM "A": Signal Invalid This DTC sets in continuous memory if the Hill Descent Control™ switch message from the IPC indicates the switch is stuck or held in place for longer than 30 seconds. This can be caused by a short to ground on the Hill Descent Control™ circuit or if there is an internal failure of the Hill Descent Control™ switch.

Possible Causes