Toyota RAV4 (XA40) 2013-2018 Service Manual: Ecm communication circuit malfunction
Description
The circuit is used to send trc and vsc control information from the skid control ecu to the ecm, and engine control information from the ecm to the skid control ecu.
Inspection procedure
Hint:
Check that the part numbers of the installed ecm and skid control ecu are correct before performing the following procedure.
- Reconfirm dtc
- Clear the dtc (see page bc-47).
- Start the engine.
- Check if the same dtc is output (see page bc-47).
Result 
Replace ecm
Zero point calibration
Description
The abs and traction actuator (skid control ecu) receives signals from the yaw rate and deceleration sensor via the can communication system. The yaw rate sensor has a built-in deceleration sensor and detects the vehicle's condition using 2 circuits (gl1, gl2). If there are problems in the bus lines between the yaw rate and deceleration sensor and the can communication system, dtcs u0123/62 (yaw rate sensor communication trouble) and u0124/95 (deceleration sensor communication trouble) are output.
The dtcs are also output when the calibration has not been completed.
Wiring diagram
Inspection procedure
Notice:
When replacing the abs and traction actuator, perform the zero point calibration (see page bc- 24).
Hint
When dtc u0123/62, u0124/95 or u0126/63 is output together with dtc c1210/36 or c1336/39, inspect and repair trouble areas indicated by dtc u0123/62, u0124/95 or u0126/63 first.
- Check yaw rate sensor installation
- Check that the yaw rate sensor has been installed properly (see page bc-211).
Ok: the sensor is tightened to the specified torque.
The sensor is not tilted.
- Perform zero point calibration of yaw rate sensor
- Perform zero point calibration of the yaw rate and deceleration sensor (see page bc-24).
- Reconfirm dtc
- Clear the dtc(s) (see page bc-47).
- Start the engine.
- Drive the vehicle and turn the steering wheel to the right and left at a speed of 45 km/h (28 mph) or more.
- Check if the same dtc(s) is recorded (see page bc- 47).
Result 
Hint:
- The dtc(s) is set if the zero point calibration has not been completed successfully.
- End the procedure when the same dtc(s) is not set after completion of the zero point calibration.
Replace abs and traction actuator assembly
Engine control system malfunction
Description
If a malfunction in the engine control system is detected, the operations of
vsc and trc are prohibited
by the fail-safe function. When the signals from the engine are input normal ...
Abs control system malfunction
Description
This dtc is output when the vsc system detects a malfunction in the abs
system.
Inspection procedure
Check dtc for abs system
Clear the dtc (see page bc-47).
Turn t ...
Other materials:
Passenger side buckle switch circuit malfunction
Description
The passenger side buckle switch circuit consists of the occupant
classification ecu and the front seat
inner belt rh.
Dtc b1771 is recorded when a malfunction is detected in the passenger side
buckle switch circuit.
Troubleshoot dtc b1771 first when dtcs b1771 and b1795 ...
If the vehicle is submerged
or water on the road is rising
This vehicle is not designed
to be able to drive on roads
that are deeply flooded with
water. Do not drive on roads
where the roads may be
submerged or the water
may be rising. It is dangerous
to remain in the vehicle,
if it is anticipated that the
vehicle will be flooded or
set adrift. Remain calm ...
Terminals of ecm
Check ecm
Measure the voltage of the ecm connector.
Hint:
Each ecm terminal's standard voltage is shown in
the table below.
In the table, first follow the information under
"condition". Look under "symbols (terminal no.)"
For the terminals to be inspected. ...
