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:
Cd player operation
Insert disc or select “cd” on the audio source selection screen
with a disc inserted to begin listening to a cd.
Audio control screen
Pressing the “audio” button displays the audio control screen from
any screens of the selected source.
Audio source selection screen
appears
Displ ...
Brake switch "B" circuit high
Description
The purpose of this circuit is to prevent the engine from stalling while
driving in the lock-up condition when
the brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signal to the ecm. Then
the ecm cancels the
operation of the lock-up clutch ...
Source voltage drop
Description
The srs is equipped with a voltage-increase circuit (dc-dc converter) in the
center airbag sensor in
case the source voltage drops.
When the source voltage drops, the voltage-increase circuit (dc-dc converter)
functions to increase the
voltage of the srs to a normal working lev ...
