2019 RAV4 New Model Technical Preview
Torque
Vectoring AWD Towing Precautions
By default, the TV-AWD system has the drivetrain connected when stopped and the rear-drive axles are always connected to the electromagnetic couplings, even when they are de-energized. Because of this special towing precautions are needed. If the rear axles are left on the ground, there is a possibility of overheating the electromagnetic couplings causing damage to the drivetrain. The vehicle should be towed with all 4 wheels lifted and it should not be Dinghy towed.
It can be towed in an
emergency for a limited distance at low speed (as listed below) with all 4
wheels on the ground. It should not ever be towed with two wheels off the
ground.
Disconnect
System Function Check and AWD Control Prevention Mode
To verify operation of the
disconnect mechanisms including solenoids and dog clutches, a Disconnect System
Function Check is available in the Utility menu of the Four-Wheel Drive ECU in
the Techstream. The utility individually connects and disconnects the front and
rear dog clutches. DO NOT drive the vehicle while using this utility or with
the drivetrain partially or completely disconnected. Drivetrain components may
be damaged.
When putting the vehicle
on a chassis dynamometer, speedometer tester or brake tester, AWD Control
Prevention Mode must be turned on. Vehicle speed on these devices should be
limited and the propeller shaft may need to be removed.
Procedure to turn on
“AWD Control Prevention Mode”:
- Remove the 4WD fuse
and enter “4WD Control Prohibited Mode”. - Check that “4WD (AWD)
TEST MODE” is displayed on the multi-information display. (Check that 4WD
control is prohibited)
To deactivate “AWD Control
Prevention Mode” simply reinstall the fuse and cancel AWD Control Prevention
Mode in the MID.
Additional
Service Procedures
Hybrid
Drivetrain
The Predictive Efficient
Drive Function uses GPS, traffic and vehicle data to analyze driving patterns,
and record specific locations where the driver frequently decelerates and
stops. When the driver approaches
one of these locations (called a stop/deceleration position), this function
assists the driver in decelerating and stopping in an eco-friendly manner.
- Demand AWD with intelligence (AWD-i) with
Auto LSD
Chassis
Newly developed TNGA trailing
wishbone rear suspensions replace torsion beam rear axles on the previous model
to achieve excellent handling stability and ride comfort.
TPWS
updates
The TPWS system has a new
direct sensing system with new features available (first seen on Camry) including
automatic sensor registration and location sensing. There are several
variations of TPWS systems and sensors available on RAV4 depending on where it
was produced. Vehicles may have the ability to register 2 sets of tires. Systems
with automatic sensor ID code registration and tire inflation pressure display
will also have location sensing function, eliminating the need to relearn tire
position after a tire rotation.
Vehicles with a full-size
spare should have 5 sensors, and compact spare should have 4. Please refer to
the repair manual and VIN inquiry for system specifics.
Automatic
Sensor Registration
When driving the vehicle,
G-sensor in the tire pressure sensor activates transmission of tire pressure
sensor information. This information is then correlated with wheel speed sensor
pulse signals to confirm sensor position.
During automatic sensor
registration, ID is confirmed through receiving synchronization signals an
average of 16 times to complete registration. Multiple confirmations are used to
prevent incorrect registration.
The tire pressure sensors
transmission intervals change based on the G forces exerted on the sensors
while driving. Transmission is low frequency (transmits every 96 seconds) while
the vehicle is stopped and goes to a lower frequency (transmits every 150
seconds) when over 8G is applied (driving over 40 km/h (25 mph)) if the vehicle
has not been stopped for at least 15 minutes before driving. The transmission
frequency slows down when the vehicle is driving to conserve sensor battery
life.
Transmission frequency
will go to high frequency (transmits every 15 seconds for the first 24 signal
transmissions) for registration if the vehicle is stopped for at least 15
minutes prior to sensor registration.
Since the transmissions
from the tire pressure sensors must synchronize an average of 16 times, it can
take a large amount of time to register the sensors if the vehicle is not
stopped for at least 15 minutes prior to pressing the ID registration switch.
When it is not practical to have the vehicle stopped for at least 15 minutes, a tire pressure sensor reading tool can
activate the high frequency transmission.
