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 built into the thermistor assembly 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 hybrid vehicle control ECU assembly. A voltage of 5 V is supplied to the thermistor assembly from the THB terminal of the hybrid vehicle control ECU assembly 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 hybrid vehicle control ECU assembly 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)

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)

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate
P0516-769	Battery Temperature Sensor Circuit Low	Malfunction in the thermistor assembly circuit (short to GND)	Thermistor assembly Wire harness or connector Hybrid vehicle control ECU assembly	Does not come on	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)	Thermistor assembly Wire harness or connector Hybrid vehicle control ECU assembly	Does not come on	Master Warning Light: Does not come on

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P0516-769

Battery Temperature Sensor Circuit Low

Malfunction in the thermistor assembly circuit (short to GND)

Thermistor assembly
Wire harness or connector
Hybrid vehicle control ECU assembly

Does not come on

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)

Thermistor assembly
Wire harness or connector
Hybrid vehicle control ECU assembly

Does not come on

Master Warning Light:

Does not come on

WIRING DIAGRAM


*a	Thermistor Assembly
*b	Hybrid Vehicle Control ECU Assembly

CAUTION / NOTICE / HINT

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 GND

PROCEDURE

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU ASSEMBLY CONNECTOR)

Check the connector connections and contact pressure of the relevant terminals for the hybrid vehicle control ECU assembly connectors.

Click here

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

for LHD

for RHD

Result

Proceed to
OK
NG

CONNECT SECURELY

READ VALUE USING GTS (AUXILIARY BATT TEMPERATURE)

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Data List / Auxiliary Batt Temperature.

Powertrain > Hybrid Control > Data List

Tester Display

Auxiliary Batt Temperature

Tester Display
Auxiliary Batt Temperature

Read the Data List.

Result

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

Turn the power switch off.

READ VALUE USING GTS (CHECK FOR SHORT) Click here

CHECK FOR INTERMITTENT PROBLEMS Click here

READ VALUE USING GTS (CHECK FOR OPEN)

*A for Hatchback

*B for Wagon

Disconnect the L51 thermistor assembly connector.
*a
Front view of wire harness connector

(to Thermistor Assembly)

Connect terminals 2 (THB) and 1 (E2) of the L51 thermistor assembly connector on the wire harness side.
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Data List / Auxiliary Batt Temperature.

Powertrain > Hybrid Control > Data List

Tester Display

Auxiliary Batt Temperature

Tester Display
Auxiliary Batt Temperature

Read the Data List.

Tester Display

Condition

Specified Condition

Auxiliary Batt Temperature

Terminals THB and E2 connected,

Power switch on (IG)

215°C (419°F)

Turn the power switch off.

Reconnect the L51 thermistor assembly connector.

Result

Proceed to
OK
NG

REPLACE THERMISTOR ASSEMBLY

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - THERMISTOR ASSEMBLY)

*a
Component with harness connected

(Hybrid Vehicle Control ECU Assembly)

Connect terminals 20 (THB) and 21 (ETHB) of the E136 hybrid vehicle control ECU assembly connector.
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Data List / Auxiliary Batt Temperature.

Powertrain > Hybrid Control > Data List

Tester Display

Auxiliary Batt Temperature

Tester Display
Auxiliary Batt Temperature

Read the Data List.

Tester Display

Condition

Specified Condition

Auxiliary Batt Temperature

Terminals THB and ETHB connected,

Power switch on (IG)

215°C (419°F)

Turn the power switch off.

Result

Proceed to
OK
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY for LHD: Click here
REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY for RHD: Click here

READ VALUE USING GTS (CHECK FOR SHORT)

*A for Hatchback

*B for Wagon

Disconnect the L51 thermistor assembly connector.
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Data List / Auxiliary Batt Temperature.

Powertrain > Hybrid Control > Data List

Tester Display

Auxiliary Batt Temperature

Tester Display
Auxiliary Batt Temperature

Read the Data List.

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

Turn the power switch off.

Reconnect the L51 thermistor assembly connector.

Result

Proceed to
OK
NG

REPLACE THERMISTOR ASSEMBLY

CHECK HARNESS AND CONNECTOR (THERMISTOR ASSEMBLY - HYBRID VEHICLE CONTROL ECU ASSEMBLY)

Disconnect the L51 thermistor assembly connector.
Disconnect the E136 hybrid vehicle control ECU assembly connector.

Front view of wire harness connector

(to Thermistor Assembly)

Rear view of wire harness connector

(to Hybrid Vehicle Control ECU Assembly)

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

Standard Resistance (Check for Open)

Tester Connection	Condition	Specified Condition
L51-2 (THB) - E136-20 (THB)	Power switch off	Below 1 Ω
L51-1 (E2) - E136-21 (ETHB)	Power switch off	Below 1 Ω

Standard Resistance (Check for Short)

Tester Connection	Condition	Specified Condition
L51-2 (THB) or E136-20 (THB) - Body ground and other terminals	Power switch off	10 kΩ or higher
L51-1 (E2) or E136-21 (ETHB) - Body ground and other terminals	Power switch off	10 kΩ or higher

Reconnect the L51 thermistor assembly connector.

Reconnect the E136 hybrid vehicle control ECU assembly connector.

Result

Proceed to
OK
NG

REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY for LHD: Click here
REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY for RHD: Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR

*A	for Hatchback
*B	for Wagon

*A	for Hatchback
*B	for Wagon