DTC P189F-00: Electrical Supply Unit (ESU) Power Supply: Low Input

P189F-00: (PCM - VIN Y) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Electrical supply unit (ESU) power supply: Low input
Detection condition	The PCM detects a short to ground or open circuit in the electrical supply unit (ESU) power supply circuit.
Fail-safe	Inhibits the i-ACTIV AWD system control.
Possible cause	Malfunction in wiring harness (including connector/terminal) between battery and electrical supply unit (ESU) (see CIRCUIT INSPECTION .) (see CONNECTOR INSPECTION .) Electrical supply unit (ESU) malfunction (Refer to applicable ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION in the service information.) PCM malfunction (Refer to applicable PCM REMOVAL/INSTALLATION (VIN Y) in the service information.)
Repeatability verification procedure	Clear the DTC recorded in the memory. (see CLEARING DTC .) Switch the ignition ON (engine off). Perform the DTC inspection for the PCM. (See DTC INSPECTION .)
Courtesy of MAZDA MOTORS CORP.
1	Battery
2	Electrical supply unit (ESU)