P0516

L110F HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0516-769,P0517-770: Battery Temperature Sensor Circuit Low
P0517-770 - Battery Temperature Sensor Circuit High

DESCRIPTION

- The auxiliary battery temperature sensor detects the auxiliary battery temperature. The resistance of the thermistor built into the auxiliary battery temperature sensor changes in accordance with changes in the auxiliary battery temperature. The lower the auxiliary battery temperature, the higher the thermistor resistance. Conversely, the higher the temperature, the lower the resistance. The auxiliary battery temperature sensor is connected to the hybrid vehicle control ECU. A voltage of 5 V is supplied to the auxiliary battery temperature sensor from the THB terminal of the hybrid vehicle control ECU through its internal resistor. This means that the resistor and the auxiliary battery temperature sensor 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 reduces the charging current when the auxiliary battery temperature is high to protect the auxiliary battery.









WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
- Read the freeze frame data using the Techstream. In the freeze frame data, some information is recorded about the engine conditions at the moment a malfunction occurred. This information can be helpful when troubleshooting.
- Characteristics of the thermistor resistance (reference values) are as follows.






PROCEDURE

1. CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

(a) Check the connections of the hybrid vehicle control ECU connectors.

OK:

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

NG -- CONNECT SECURELY
OK -- Continue to next step.

2. CHECK CONNECTOR CONNECTION CONDITION (BATTERY TEMPERATURE SENSOR CONNECTOR)

(a) Check the connection of the battery temperature sensor connector.





OK:

The connector is connected securely and there are no contact problems.

NG -- CONNECT SECURELY
OK -- Continue to next step.

3. INSPECT BATTERY (BATTERY TEMPERATURE SENSOR)

(a) Disconnect the battery (battery temperature sensor) connector.

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





Standard resistance:





HINT
The battery temperature sensor is not available separately. If it requires replacement, replace the auxiliary battery.

NG -- REPLACE BATTERY Components
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BATTERY TEMPERATURE SENSOR)

(a) Disconnect connectors A75 and A74 from the hybrid vehicle control ECU.





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

Standard resistance (Check for open):





Standard resistance (Check for short):





(c) Turn the power switch on (IG).

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

Standard voltage:





NOTICE:
Turning the power switch on (IG) with the hybrid vehicle control ECU connectors disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE HYBRID VEHICLE CONTROL ECU Components