HYBRID CONTROL SYSTEM, Diagnostic DTC:P0516-769, P0517-770

DTC Code DTC Name
P0516-769 Battery Temperature Sensor Circuit Low
P0517-770 Battery Temperature Sensor Circuit High

DESCRIPTION

The thermistor assembly detects the auxiliary battery temperature. The resistance of the thermistor assembly built into the thermistor changes in accordance with changes in the auxiliary battery temperature. The lower the auxiliary battery temperature, the higher the thermistor assembly resistance. Conversely, the higher the temperature, the lower the resistance. The thermistor assembly is connected to the EV control ECU. A voltage of 5 V is supplied to the thermistor assembly from the THB terminal of the EV control ECU through its internal resistor R. This means that resistor R and the thermistor assembly are connected in series. The voltage at the THB terminal and the resistance value change in accordance with changes in the auxiliary battery temperature. Based on this signal, the EV control ECU reduces the charging current when the auxiliary battery temperature is high to protect the auxiliary battery.

Tech Tips

Characteristics of the thermistor assembly resistance (reference values) are as follows.

Terminal

THB

(with Connector Disconnected)

 Resistance Ambient Temperature
THB - E2 4.5 to 5.5 V 3.00 to 3.73 kΩ Approximately 10°C (50°F)
1.60 to 1.80 kΩ Approximately 25°C (77°F)
0.80 to 1.00 kΩ Approximately 40°C (104°F)
A01MJDKE03
DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate
P0516-769 Battery Temperature Sensor Circuit Low

Malfunction in the thermistor assembly circuit (short to ground)

(1 trip detection logic)

  • Thermistor assembly

  • Wire harness or connector

  • EV control ECU

Master Warning Light:

Does not come on
P0517-770 Battery Temperature Sensor Circuit High

Malfunction in the thermistor assembly circuit (open or short to +B)

(1 trip detection logic)

  • Thermistor assembly

  • Wire harness or connector

  • EV control ECU

Master Warning Light:

Does not come on
Related Data List
DTC No. Data List
P0516-769 Auxiliary Battery Temperature
P0517-770

WIRING DIAGRAM

A01MG81E27
*a Thermistor Assembly
*b EV Control ECU

CAUTION / NOTICE / HINT

Note

When the vehicle is parked with the power switch off, if the FC control ECU judges that the FC stack temperature will go below 0°C (32°F), it activates the FC air compressor, hydrogen pump and FC cooling water pump for a maximum of 180 seconds and drains water from the FC stack assembly. When performing inspection or repairs with the power switch off (not on (IG) or on (READY)), disconnect the cable from the negative (-) auxiliary battery terminal before performing work (If the auxiliary battery voltage is needed to conduct inspection, warm up the FC system beforehand).

Tech Tips


  • Read the freeze frame data using the GTS. In the freeze frame data, some information is recorded about the vehicle conditions at the moment a malfunction occurred. This information can be helpful when troubleshooting.

  • After confirming that DTC P0516-769 or P0517-770 is output, use the GTS to check "Auxiliary Batt Temperature" in the Hybrid Control Data List.

    Displayed Temperature Malfunction
    -40°C (-40°F) Open circuit or short to +B
    215°C (419°F) Short circuit or short to ground

  • After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


    1. Turn the power switch on (IG) and wait for 5 seconds or more.

PROCEDURE


  1. CHECK CONNECTOR CONNECTION CONDITION (EV CONTROL ECU CONNECTOR)


    1. A01MGTOC01
      *A for LHD
      *B for RHD

      Check the connector connections and contact pressure of the relevant terminals for the EV control ECU connectors.

      Click here

      OK
      The connectors are connected securely and there are no contact pressure problems.
      Result
      Proceed to
      OK
      NG

    NG

    CONNECT SECURELY

    OK

  2. READ VALUE USING GTS (AUXILIARY BATT TEMPERATURE)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / EV / Data List / Auxiliary Batt Temperature.


      Powertrain > EV > Data List
      Tester Display
      Auxiliary Battery Temperature

    4. Read the Data List.

      Result
      Result Proceed to
      -40°C (-40°F) A
      215°C (419°F) B
      Same as actual temperature C

    5. Turn the power switch off.


    B

    READ VALUE USING GTS (CHECK FOR SHORT) Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  3. READ VALUE USING GTS (CHECK FOR OPEN)


    1. A01MH1K

      Disconnect the thermistor assembly connector.

    2. A01MFNSC28
      *a

      Front view of wire harness connector

      (to Thermistor Assembly)

      Connect terminals 2 (THB) and 1 (E2) of the thermistor assembly connector.

    3. Connect the GTS to the DLC3.

    4. Turn the power switch on (IG).

    5. Enter the following menus: Powertrain / EV / Data List / Auxiliary Batt Temperature.


      Powertrain > EV > Data List
      Tester Display
      Auxiliary Battery Temperature

    6. Read the Data List.

      OK
      Tester Display Condition Specified Condition
      Auxiliary Batt Temperature

      Terminals Q13-1 and Q13-2 connected

      Power switch on (IG)

      		 215°C (419°F)

    7. Turn the power switch off.

    8. Reconnect the thermistor assembly connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE THERMISTOR ASSEMBLY Click here

    NG

  4. CHECK HARNESS AND CONNECTOR (EV CONTROL ECU - THERMISTOR ASSEMBLY)


    1. A01MG4FC88
      *a

      Component with harness connected

      (EV Control ECU)

      Connect terminals 20 (THB) and 21 (ETHB) of the EV control ECU connector.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Enter the following menus: Powertrain / EV / Data List / Auxiliary Batt Temperature.


      Powertrain > EV > Data List
      Tester Display
      Auxiliary Battery Temperature

    5. Read the Data List.

      OK
      Tester Display Condition Specified Condition
      Auxiliary Battery Temperature

      Terminals G46-20 (THB) and G46-21 (ETHB) connected

      Power switch on (IG)

      		 215°C (419°F)

    6. Turn the power switch off.

      Result
      Proceed to
      OK
      NG

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG

    REPLACE EV CONTROL ECU Click here

  5. READ VALUE USING GTS (CHECK FOR SHORT)


    1. A01MH1K

      Disconnect the Q13 thermistor assembly connector.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Enter the following menus: Powertrain / EV / Data List / Auxiliary Batt Temperature.


      Powertrain > EV > Data List
      Tester Display
      Auxiliary Battery Temperature

    5. Read the Data List.

      OK
      Tester Display Condition Specified Condition
      Auxiliary Battery Temperature Power switch on (IG) -40°C (-40°F)

    6. Turn the power switch off.

    7. Reconnect the thermistor assembly connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE THERMISTOR ASSEMBLY Click here

    NG

  6. CHECK HARNESS AND CONNECTOR (THERMISTOR ASSEMBLY - EV CONTROL ECU)


    1. Disconnect the thermistor assembly connector.

    2. Disconnect the EV control ECU connector.

    3. A01MGNNC10
      *a

      Front view of wire harness connector

      (to Thermistor Assembly)
      *b

      Rear view of wire harness connector

      (to EV Control ECU)

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q13-2 - G46-20 (THB) Power switch off Below 1 Ω
      Q13-1 - G46-21 (ETHB) Power switch off Below 1 Ω
      Q13-2 or G46-20 (THB) - Body ground and other terminals Power switch off 10 kΩ or higher
      Q13-1 or G46-21 (ETHB) - Body ground and other terminals Power switch off 10 kΩ or higher

    4. Reconnect the EV control ECU connector.

    5. Reconnect the thermistor assembly connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE EV CONTROL ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR