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

P189F: 00 (PCM (PYUL)) 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 [ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION ] in service information). PCM malfunction (Refer to [PCM REMOVAL/INSTALLATION ] in service information).
Repeatability verification procedure	Clear the DTC recorded in the memory. (See CLEARING DTC .) Switch the ignition ON (engine off).
Courtesy of MAZDA MOTORS CORP.
1	Battery
2	Electrical supply unit (ESU)