DTC    P0A02-719    Motor Electronics Coolant Temperature Sensor Circuit Low

DTC    P0A03-720    Motor Electronics Coolant Temperature Sensor Circuit High

for Preparation Click here


DESCRIPTION

The HV control ECU detects HV coolant temperature through the coolant temperature sensor built into the inverter. The inverter cooling system is the same as that for the Motor or Generator, and operates independently of the engine cooling system. The HV control ECU controls the inverter cooling system to prevent overheating based on signals from the coolant temperature sensor. The ECU also monitors cooling system operation and detects malfunctions in the HV coolant temperature sensor and the circuit.

DTC No.
INF Code
DTC Detection Condition
Trouble Area
P0A02
719
GND short in HV coolant temperature sensor circuit
  1. w/ converter inverter assembly (MG ECU)
P0A03
720
Open or +B short in HV coolant temperature sensor circuit
  1. w/ converter inverter assembly (MG ECU)

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.

  1. 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. Be sure to 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.



    A103665E03

  1. Check the connections of the MG ECU connectors.

    OK:
    Connectors are connected securely and there is no poor connection.



OK
REPLACE W/ CONVERTER INVERTER ASSEMBLY
NG

CONNECT SECURELY