Some 2020 Lincoln Aviator vehicles built on or before Nov. 30, 2019, may exhibit an illuminated ABS warning indicator lamp with DTC C0020 stored in the ABS module. 

It may not be necessary to replace the ABS module/hydraulic control unit (HCU) to resolve the DTC. 

The problem may be due to a poor ground connection and/or improper plating on the attachment bolts at G108. 

To correct the condition, replace and properly tighten the ground cable fasteners, P/N A505255. Tighten the new fasteners securing the ground cables to 106 in.-lbs.

Apply Motorcraft electrical grease XG-12 (or equivalent) to the fastener and ground cable eyelet. Clear any DTCs.

Ground cable bolt locations. Do not strip paint to achieve ground. Ground will be obtained via the bolt threads.