P0A94-589

DESCRIPTION

The MG ECU uses a voltage sensor that is built into the boost converter to detect pre-boost high voltage (VL) for boost control. The boost converter voltage sensor outputs a voltage that varies between 0 and 5 V in accordance with changes in the high voltage. The higher the high voltage, the higher the output voltage. Conversely, the lower the high voltage, the lower the output voltage. The MG ECU monitors the boost converter voltage sensor signal line and detects a malfunction.

DTC No.	INF Code	DTC Detection Condition	Trouble Area
P0A94	589	Open or GND short in boost converter voltage (VL) sensor circuit	Wire harness or connector w/ converter inverter assembly (MG ECU)
↑	590	+B short in boost converter voltage (VL) sensor circuit	Wire harness or connector w/ converter inverter assembly (MG ECU)

MONITOR DESCRIPTION

The MG ECU monitors the boost converter voltage (VL) sensor circuit. If the MG ECU detects an open or short malfunction of the VL sensor circuit, the HV control ECU illuminates the MIL and sets a DTC.

INSPECTION PROCEDURE

CAUTION:

1. Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
   
2. After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals.
   

HINT:

At least 5 minutes is required to discharge the high-voltage capacitor inside the w/ converter inverter assembly.

1. CHECK CONNECTION CONDITION OF MG ECU CONNECTOR (LOOSENESS AND POOR CONTACT)

CAUTION:

Be sure to wear insulated gloves.

1. Turn the ignition switch off and remove the service plug grip. (Click here)

   NOTICE:

   Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.

2. Remove the inverter cover. (Click here)

   NOTICE:

   1. Wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
      
   2. Prevent water in the reservoir tank from entering the inverter.
      
   3. Removing the inverter cover causes the MG ECU board to be exposed. Therefore, temporarily install the inverter cover for each area to be inspected.
      

3. Check the connections of the MG ECU connectors.

   OK:

   Connectors are connected securely and there is no poor connection.
   

NG	CONNECT SECURELY

OK
REPLACE W/ CONVERTER INVERTER ASSEMBLY