Toyota RAV4 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:
Communication
Description
When a key is inserted into the ignition key cylinder but no communication
occurs between the key and
transponder key ecu, dtc b2796 is output. When a key is inserted into the
ignition key cylinder but a
communication error occurs between the key and transponder key ecu, dtc b ...
PDC Park Distance Control- Warning
Signal tones
General information
An intermittent tone indicates when the vehicle
is approaching an object. E.g., when an object is
detected to the left rear of the vehicle, a signal
tone sounds from the left rear speaker.
The shorter the distance to the object, the
shorter the intervals.
When the ...
Intermediate shaft speed sensor "A"
Description
This sensor detects the rotation speed of the counter gear. By comparing the
counter gear speed signal
(nc) with the direct clutch speed sensor signal (nt), the ecm detects the shift
timing of the gears and
approximately controls the engine torque and hydraulic pressure accord ...
