DTC U0320-00, U0420-00, U0420-64: Abnormal Message From EPS Control Module: Notes

WARNING: This page is about a different car, the 2018 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0320:00/U0420:00/U0420:64 (DYNAMIC STABILITY CONTROL (DSC)) DETECTION CONDITION AND POSSIBLE CAUSE

DTC	U0320:00, U0420:00, U0420:64	Abnormal Message From EPS Control Module
DETECTION CONDITION		U0320:00, U0420:00 Correct data cannot be received from EPS control module. U0420:64 While driving at a vehicle speed of 20-65 km/h {13-40 mph} or more, the signal from the steering angle sensor remains unchanged when the steering angle is turned to the right and left.
FAIL-SAFE FUNCTION		Refer to "Fail-safe Function Malfunction Contents". (See DTC TABLE (DYNAMIC STABILITY CONTROL (DSC)) .)
POSSIBLE CAUSE		EPS control module malfunction
SYSTEM WIRING DIAGRAM		Not applicable