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:
Engine immobiliser system malfunction
Description
This dtc is output when one of the following occurs: 1) the ecm detects
errors in its own
communications with the transponder key ecu; 2) the ecm detects errors in the
communication lines; or
3) the ecu communication id between the transponder key ecu and ecm is different
an ...
Road test
Problem symptom confirmation
Based on the result of the customer problem
analysis, try to reproduce the symptoms. If the
problem is that the transaxle does not shift up, shift
down, or the shift point is too high or too low,
conduct the following road test referring to the
automat ...
Registration
Perform vehicle stability control system recognition in ecm
Notice:
If the vehicle has both cruise control and vsc, when
replacing ecm, perform vsc recognition as follows:
Turn the ignition switch on.
After waiting approximately 5 seconds, turn the
cruise control main switch on.
Ke ...