INAPPROPRIATE OPERATION AND CONTROL RECORD 0x42 (UNUSUAL CONNECTION WITH A GENERATOR): Notes
WARNING: This page is about a different car, the 2017 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Inappropriate operation and control code 0x42 is more likely to be recorded than DTC P2503:00. Inappropriate operation and control code 0x42 may be recorded when the operation conditions are met due to signal noise. Therefore, if there is no malfunction in the related part, do not replace the part.