Normal Operation

WARNING: This page is about a different car, the 2014 Lincoln MKX and 2014 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

The ABS module uses an internal solid state switch to operate the ABS pump motor. The ABS module tests the ABS pump motor by activating it for 30 milliseconds. While the pump motor is being activated, the ABS module monitors the voltage drop across the ABS pump motor solid state switch and the amount of current the ABS pump motor draws through the solid state switch. If the voltage drop is too high or if the ABS pump motor is drawing too much current, the ABS module sets a DTC. After 30 milliseconds have passed, the ABS module stops applying voltage to the pump motor and observes the voltage that the spinning ABS pump motor is generating. The voltage generated by the motor indicates how fast the motor is spinning. Voltage that is too low indicates the motor is not spinning freely and a DTC sets.

Fused battery voltage from Battery Junction Box (BJB) fuse 5 (40A) is used by the ABS module to power the ABS pump motor. The ABS module provides ground for the ABS pump motor. Insufficient power or ground along these circuits causes multiple DTCs to set.

C0020:13 (ABS Pump Motor Control: Circuit Open) - this DTC sets if the voltage supplied to the ABS module is less than 10 volts, if there is an open or high resistance on the ABS pump motor circuit between the ABS module and the Hydraulic Control Unit (HCU), or if the ABS module is faulted internally.
C0020:71 (ABS Pump Motor Control: Actuator Stuck) - this DTC sets if the ABS module detects the ABS pump motor is not rotating when it is commanded to run.

This pinpoint test is intended to diagnose the following:

Fuse
Wiring, terminals or connectors
HCU
ABS module