DTC U0198-00: Communication Error With MAZDA Emergency Assistance Control Module [Audio Control Unit (ACU)]: Outline

DTC U0198:00 (AUDIO CONTROL UNIT (ACU)) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Communication error with Mazda EMERGENCY ASSISTANCE control module
Detection condition	The audio control unit (ACU) detects a communication interruption or a communication error with Mazda EMERGENCY ASSISTANCE control module for approx. 30 s.
Fail-safe	Not applicable
Possible cause	Mazda EMERGENCY ASSISTANCE control module connector or terminal malfunction Short to ground or open circuit in Mazda EMERGENCY ASSISTANCE control module power supply circuit Open circuit in Mazda EMERGENCY ASSISTANCE control module ground circuit Audio control unit (ACU) connector or terminal malfunction Short to power supply, short to ground or open circuit in the circuits between the following audio control unit (ACU) and Mazda EMERGENCY ASSISTANCE control module Power supply circuit Signal circuit Ground circuit Malfunction in shield wire of circuits between audio control unit (ACU) and Mazda EMERGENCY ASSISTANCE control module Mazda EMERGENCY ASSISTANCE control module malfunction Audio control unit (ACU) malfunction
Courtesy of MAZDA MOTORS CORP.