DTC U0515-41: Error Signal Received From Start Stop Unit (BCM): Notes

WARNING: This page is about a different car, the 2020 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0515:41 (BCM) DETECTION CONDITION AND POSSIBLE CAUSE

Description	Error signal received from start stop unit
Detection condition	Check sum error occurred on communication with the BCM and the start stop unit 3 times continuously with the ignition switched ON (engine off or on).
Fail-safe	Exterior lighting system Turn the TNS (parking lights) and headlights LO on, and turn off other exterior light controls. Auto light system Continue the controls prior to the auto light malfunction detection. Wiper system Continue the controls prior to the wiper malfunction detection. Washer system Stop the washer control. Auto wiper system Continue the controls prior to the wiper malfunction detection.
Possible cause	DTCs are stored in the start stop unit. Start stop unit malfunction BCM malfunction
System wiring diagram	Not applicable