DTC B1252-87: Communication Error With Audio Control Unit (ACU) [MAZDA Emergency Assistance Control Module]: Outline

DTC B1252:87 (MAZDA EMERGENCY ASSISTANCE CONTROL MODULE) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Communication error with audio control unit (ACU)
Detection condition	The Mazda EMERGENCY ASSISTANCE control module cannot receive a signal from the audio control unit (ACU) for 5 min or more.
Fail-safe	Not applicable
Possible cause	DTCs are stored in the audio control unit (ACU). Audio control unit (ACU) connector or terminal malfunction Mazda EMERGENCY ASSISTANCE control module connector or terminal malfunction Open circuit in audio control unit (ACU) signal circuit Mazda EMERGENCY ASSISTANCE control module malfunction
Courtesy of MAZDA MOTORS CORP.