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Pinpoint Test E : DTC U0121: Notes

WARNING: This page is about a different car, the 2018 Lincoln Navigator. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0121 

Refer to Wiring Diagram Module Communications Network for schematic and connector information.

Normal Operation and Fault Conditions 

GSM: DTC Fault Trigger Conditions 

DTC Description Fault Trigger Conditions
U0121 Lost Communication With Anti-Lock Brake System Control Module Sets in continuous memory in the GSM if data messages received from the ABS are missing for 5 seconds or longer.

Possible Sources