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

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 power management control ECU. A voltage of 5 V is supplied to the thermistor assembly from the THB terminal of the power management 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 power management 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)

  

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR)

   
   

   1. 

      Check the connector connections and contact pressure of the relevant terminals for the power management control ECU connectors Click here.

      OK
      The connectors are connected securely and there are no contact pressure problems.

   
   

   NG

   CONNECT SECURELY

   OK

2. READ VALUE USING TECHSTREAM (AUXILIARY BATT TEMPERATURE)

   
   

   1. Connect the Techstream to the DLC3.

   2. Turn the power switch on (IG).

   3. Enter the following menus: Powertrain / Hybrid Control / Data List / Auxiliary Batt 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 TECHSTREAM (CHECK FOR SHORT) Click here

   C

   CHECK FOR INTERMITTENT PROBLEMS Click here

   A

3. READ VALUE USING TECHSTREAM (CHECK FOR OPEN)

   
   

   1. 

      Disconnect connector O26 from the thermistor assembly.

   2. 

      Connect terminals 2 (THB) and 1 (E2) of vehicle side connector O26 of the thermistor assembly.

   3. Connect the Techstream to the DLC3.

   4. Turn the power switch on (IG).

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

   6. Read the Data List.

      OK
      Tester Display Condition Specified Condition Auxiliary Batt Temperature Terminals THB and E2 connected. Power switch on (IG) 215°C (419°F)

      Text in Illustration

      *a	Front view of wire harness connector (to Thermistor Assembly)

   7. Turn the power switch off.

   8. Connect the thermistor assembly connector.

   
   

   NG

   CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - THERMISTOR ASSEMBLY) Click here

   OK

   REPLACE THERMISTOR ASSEMBLY

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

   
   
   1. 

      Text in Illustration

      *a	Component with harness connected (Power Management Control ECU)

      Connect terminals 28 (THB) and 30 (ETHB) of connector I3 of the power management control ECU.

   2. Connect the Techstream to the DLC3.

   3. Turn the power switch on (IG).

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

   5. Read the Data List.

      OK
      Tester Display Condition Specified Condition Auxiliary Batt Temperature Terminals THB and ETHB connected. Power switch on (IG) 215°C (419°F)

   6. Turn the power switch off.

   
   

   NG

   REPLACE POWER MANAGEMENT CONTROL ECU Click here

   OK

   REPAIR OR REPLACE HARNESS OR CONNECTOR

5. READ VALUE USING TECHSTREAM (CHECK FOR SHORT)

   
   

   1. 

      Disconnect connector O26 from the thermistor assembly.

   2. Connect the Techstream to the DLC3.

   3. Turn the power switch on (IG).

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

   5. Read the Data List.

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

   6. Turn the power switch off.

   7. Connect the thermistor assembly connector.

   
   

   NG

   CHECK HARNESS AND CONNECTOR (THERMISTOR ASSEMBLY - POWER MANAGEMENT CONTROL ECU) Click here

   OK

   REPLACE THERMISTOR ASSEMBLY

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

   
   

   1. Disconnect connector O26 from the thermistor assembly.

   2. 

      Text in Illustration

      *a	Front view of wire harness connector (to Thermistor Assembly)
      *b	Rear view of wire harness connector (to Power Management Control ECU)

      Disconnect connector I3 from the power management control ECU.

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

      Standard Resistance (Check for Open)
      Tester Connection Switch Condition Specified Condition O26-2 (THB) - I3-28 (THB) Power switch off Below 1 Ω O26-1 (E2) - I3-30 (ETHB) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)
      Tester Connection Switch Condition Specified Condition O26-2 (THB) or I3-28 (THB)- Body ground and other terminals Power switch off 10 kΩ or higher O26-1 (E2) or I3-30 (ETHB)- Body ground and other terminals Power switch off 10 kΩ or higher

   4. Connect the thermistor assembly connector.

   5. Connect the power management control ECU connector.

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

   REPLACE POWER MANAGEMENT CONTROL ECU Click here