DTC U0338 09: Error Light Switch Signal Received From Start Stop Unit: Notes

WARNING: This page is about a different car, the 2014 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0338 09 DETECTION CONDITION AND POSSIBLE CAUSE

Description	Error light switch signal received from start stop unit
Detection condition	Front body control module (FBCM) receives the CAN error signals from the start stop unit 3 times continuously with the ignition switched ON (engine off or on).
Fail-safe function	If DTC U0338:09 is detected when the ignition is switched ON (engine off or on), the headlight LO and the TNS are illuminated. If DTC U0338:09 is cleared, the headlight LO and the TNS are turned off, and the operation returns to normal.
Possible cause	Light switch malfunction Start stop unit malfunction Front body control module (FBCM) malfunction
System wiring diagram	Not applicable