Toyota RAV4 (XA40) 2013-2018 Service Manual: Battery temperature sensor circuit
Description
The battery temperature sensor installed on the battery current sensor detects battery temperature.
A thermistor is integrated into the battery temperature sensor, and the resistance in the battery temperature sensor changes according to the battery temperature.
The resistance of the thermistor in the battery temperature sensor decreases as the battery temperature increases. The resistance increases as the temperature decreases.
The battery temperature sensor is connected to the ecm. The ecm supplies 5 v from the thb terminal to the battery temperature sensor through resistor r.
The battery temperature sensor and resistor r are connected in series. This results in fluctuations in the voltage supplied from the thb terminal when the resistance changes according to the battery temperature.
The ecm determines the battery temperature according to fluctuations in voltage. When the battery temperature is high, the ecm determines to reduce the amount of current supplied from the generator in order to protect the battery.
Wiring diagram
Refer to dtc p1550 (see page es-262)
Inspection procedure
- Inspect battery current sensor
- Disconnect the b29 battery current sensor connector.
- Measure the resistance.
Standard resistance 
- Check harness and connector (battery current sensor - ecm)
- Disconnect the b29 battery current sensor connector.
- Disconnect the b30 ecm connectors.
- Measure the resistance of the wire harness side connectors.
Standard resistance (check for open)
Standard resistance (check for short)
Cold start
Description
The electronic throttle control system (etcs) controls the engine idling
speed. The etcs operates the
throttle actuator to open and close the throttle valve, and adjusts the intake ...
System voltage
Description
The battery supplies electricity to the ecm even when the ignition switch is
in the off position. This
power allows the ecm to store data such as dtc history, freeze frame data and ...
Other materials:
On-vehicle inspection
Check ignition coil assembly and perform spark test
Notice:
in this section, the terms "cold" and "hot" refer to
the temperature of the coils. "Cold" means
approximately -10 to 50°c (14 to 122°f). "Hot" means
approximately 50 to 100°c (122 to 212 ...
Disassembly
Remove radio setting condenser
Remove the bolt and condenser.
Remove oil pressure switch
Using a 24 mm deep socket wrench, remove the sensor.
Remove engine coolant temperature sensor
Using sst, remove the sensor and gasket.
Sst 09817-33190
Remove c ...
Removal
Disconnect cable from negative battery terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove mass air flow meter
Disconnect the mass air flow meter connector.
...
