
Traffic Jam Assist (TJA)*
▼Tra ffi c
Jam Assist (TJA)
The TJA is a system which consists of a
headway control function and a
steering assist function for reducing
driver fatigue during traffic jams when
driving on expressways or highways.
This system performs headway control
to maintain a constant distance
between your vehicle and a vehicle
ahead at a preset vehicle speed
without you having to use the
accelerator or brake pedal. Even
further, with the steering assist
function, when vehicle lane lines are
detected, the function assists the driver
in keeping the vehicle within the lane
lines. If lane lines are not detected, the
function provides the driver driving
assistance in keeping the vehicle along
the motion path with the vehicle
ahead.
WARNING
Do not rely completely on TJA:
The TJA is not an automated driving
system. In addition, the functions
have limitations. Do not rely
completely on the system and always
stay on course using the steering
wheel.
Set a vehicle speed within the speed
limit according to the road
conditions and the weather
conditions.
The TJA may not be able to detect a
vehicle ahead depending on the type
of vehicle ahead and its conditions,
the weather conditions, and the road
conditions. Additionally, the system
might be unable to decelerate
sufficiently if a vehicle ahead applies
the brakes suddenly, another vehicle
cuts into the driving lane, or the difference in vehicle speed between
your vehicle and the vehicle ahead is
larger, which could result in an
accident. Check the surrounding
conditions and always drive carefully
while keeping a safe distance from
vehicles ahead and on-coming
vehicles.
For the purposes of safety, switch the
TJA off when it is not being used.
Leaving the TJA turned on when it is
not in use is dangerous as it could
operate unexpectedly, resulting in an
accident.
Do not use the TJA under the
following conditions. Otherwise, it
may result in an accident.
General roads other than
expressways or highways (Driving
under these conditions using the TJA
is not possible.)
Roads with sharp curves and where
vehicle traffic is heavy with
insufficient space between vehicles,
or roads where frequent and
repetitive acceleration and
deceleration occur (Driving under
these conditions using the TJA is not
possible).
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When entering and exiting
interchanges, service areas, and
parking areas of expressways (If you
exit an expressway while headway
control is in use, the vehicle ahead
will no longer be tracked and your
vehicle may accelerate to the set
speed).
Slippery roads such as icy or
snow-covered roads (Tires could spin
causing you to lose vehicle control,
or the stop hold control may not
operate.)
Long, descending slopes (to
maintain distance between vehicles,
the system automatically and
continuously applies the brakes
which could result in the loss of
brake power.)
Two-wheeled vehicles such as
motorcycles or bicycles are ahead.
Slopes with a steep gradient (The
vehicle ahead may not be detected
correctly, your vehicle may slip while
stopped by the stop hold control, or
it may accelerate suddenly after it
starts moving.)
Driving under bad weather
conditions (rain, fog, and snow).
The vehicle is driven on slippery
roads such as icy or snow-covered
roads and unpaved roads (Tires
could spin causing you to lose
vehicle control, or the stop hold
control may not operate.)
Tires of a different specified size are
used, such as a temporary spare tire.
Tires with
insufficient tread are used.
The tire pressures are not adjusted to
the specified pressure.
The vehicle is being used to tow a
camper or boat trailer.
Tire chains are used.The vehicle is driven on roads with
lane lines other than white (yellow)
lines, such as an expressway.
Do not get out of the vehicle while
the stop hold control is operating.
Getting out of the vehicle while the
stop hold control is operating is
dangerous as the vehicle may move
unexpectedly and result in an accident.
Before getting out of the vehicle,
switch the TJA off, apply the parking
brake, and then shift the selector lever
to the P position.
CAUTION
Turn the system off when the vehicle is
running on a chassis roller.
Heed the following cautions so that
the TJA can operate normally.
Turn the system off when the vehicle
is running on a chassis roller.
Do not modify the vehicle's
suspensions.
Always use wheels of the specified
size for the front and rear wheels.
Consult an Authorized Mazda Dealer
for tire replacement.
NOTE
The headway control does not detect
the following as physical objects.
Vehicles approaching in the
opposite direction
Pe de st r ia nsStationary objects (stopped
vehicles, obstructions)
If a vehicle ahead is traveling at an
extremely low speed, the system may
not detect it correctly.
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If there is a structure on the road or
an object (such as a monorail) at a
low height off the ground in front of
the vehicle, the system may operate.
Therefore, do not use the TJA.
Do not use the TJA under conditions
in which close proximity warnings
are frequently activated.
If it is necessary to accelerate for a
lane change or the vehicle ahead
brakes suddenly causing you to close
in on the vehicle rapidly, accelerate
using the accelerator pedal or
decelerate using the brake pedal
depending on the conditions.
While the TJA is in use, any intended
engine braking does not occur even
if you shift the selector lever. If
deceleration is required, lower the
vehicle speed setting or depress the
brake pedal.
While braking by the TJA control is
operating, you might hear an
operation sound, however, this does
not indicate a problem.
The brake lights turn on while
braking by the TJA control is
operating, however, they may not
turn on while the vehicle is on a
down slope at the set vehicle speed
or traveling at a constant speed and
following a vehicle ahead.
Under the following conditions, the
TJA may not be able to detect white
(yellow) lines or vehicles ahead
correctly and the TJA may not
operate normally.
The forward sensing camera (FSC)
cannot recognize the area in front
of the vehicle due to soiling or fog.
The white (yellow) lane lines are
less visible because of dirt or paintflaking.
White (yellow) lane lines or
vehicles ahead are less visible
because of bad weather (rain, fog ,
or snow).
The vehicle is driven on a
temporary lane or section with a
closed lane resulting from
construction where there might be
multiple white (yellow) lane lines,
or they are interrupted.
The camera picks up an obscure
line, such as a temporary line being
used for construction, or because
of shade, unmelted snow, or
grooves filled with water.
The road surface is wet and shiny
after rain, or there are puddles on
the road.
Heavy luggage is loaded in the
luggage compartment or on the
rear seat causing the vehicle to tilt.
A vehicle in front of your vehicle is
running near a white (yellow) lane
line making it less visible.
The windshield is dirty or foggy.The vehicle is driven through an
intersection, a junction, or a fork in
the road.
While white (yellow) lane lines
cannot be detected due to road or
weather conditions.
The surrounding brightness
suddenly changes such as when
entering or exiting a tunnel.
The illumination of the headlights
is weakened because of dirt or the
optical axis is deviated at night.
Back-light is reflected off the road
surface or the road surface is wet
and shiny after rain.
The shade of a guardrail parallel to
a white (yellow) lane line is cast on
the road.
The width of a lane is excessively
narrow or wide.
The road is excessively uneven.
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If there is a problem with the TJA, a
message is displayed on the
multi-information display. Check the
details of the problem on the center
display and then have your vehicle
inspected by an Authorized Mazda
Dealer.
Refer to If a Warning Light Turns On or
Flashes on page 7-20.▼Close Proximity Warning
If your vehicle rapidly closes in on the
vehicle ahead while you are traveling
under headway control, the warning
sound is activated and the brake
warning is indicated on the display.
Keep a safe distance between your
vehicle and a vehicle ahead.
1. “Depress Brake Pedal” message is
displayed
NOTE
In the following cases, the warnings
and brakes may not operate even if
your vehicle starts closing in on the
vehicle ahead.
You are driving your vehicle at the
same speed as the vehicle ahead.
Directly after the TJA operates.Directly after the accelerator pedal is
released.
Another vehicle cuts into the driving
lane in front of you.
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▼Setting the System
Operation conditions
Headway control function
The TJA operates when all of the following conditions are met.
The vehicle speed is about 0 km/h (0 mph) to 145 km/h (90 mph).The selector lever is in the D or M position (manual mode).The TJA is operating.The headway control function of the Mazda Radar Cruise Control (MRCC) or
Mazda Radar Cruise Control with Stop
& Go function (MRCC with Stop & Go
function) is set to operable (if it was set to inoperable, set it to operable using the
personalization function).
The brake pedal is not depressed.The parking brake is released (Electric Parking Brake (EPB) indicator light is turned
off).
There is no problem with the DSC.All the doors are closed.The driver's seat belt is fastened.
NOTE
Under the following conditions, the TJA cannot be used when the vehicle speed is
30 km/h (19 mph) or slower.
There is a problem with the stop hold control function.There is a problem with the Electric Parking Brake (EPB).The TJA may not launch directly after the engine starts.
Steering assist function
The steering assist function operates when all of the following conditions are met.
Your vehicle is moving and less than about 56 km/h (35 mph).White (yellow) lane lines on both sides are detected and you are driving near the
center of the lane, or your vehicle detects a vehicle ahead.
The steering wheel is not turned sharply.The turn signal lever is not operated.The headway control function is operating.
NOTE
The steering assist function operates so that the vehicle remains near the center of
the driving lane, however, depending on conditions such as the road curvature,
road slope and undulations, and vehicle speed, the function might not be able to
keep the vehicle near the center of the driving lane.
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When the ignition is switched OFF, the system status before it was turned off is
maintained. For example, if the ignition is switched OFF with the TJA operable, the
TJA remains operational the next time the ignition is switched ON.
When the TJA switch is pressed while the Mazda Radar Cruise Control (MRCC) or
the Mazda Radar Cruise Control with Stop & Go function (MRCC with Stop & Go
function) system is operating, the TJA operates. In addition, when the MRCC
switch is pressed while the TJA is operating, the Mazda Radar Cruise Control
(MRCC) or the Mazda Radar Cruise Contro l with Stop & Go function (MRCC with
Stop & Go function) system operates.
Changing the set vehicle speed
(To accelerate/decelerate using the RES switch)
When the RES switch is pressed up (SET+), the vehicle accelerates and when the RES
switch is pressed down (SET-), it decelerates.
Press and release immediately: 1 km/h (1 mph)Press and hold: 10 km/h (5 mph)
(To increase speed using accelerator pedal)
Depress the accelerator pedal and press the RES switch up (SET+) or down (SET-) at
the desired speed. If the switch is not operated, the system returns to the set speed
after you release your foot from the accelerator pedal.
NOTE
The warnings and brake control do not operate while depressing the accelerator
pedal.
The lowest possible speed which can be set on the TJA is 30 km/h (19 mph).The vehicle speed setting can be changed by operating the RES switch during stop
hold control.
Changing the distance between vehicles during headway control
The distance-between-vehicles can be set to 4 levels; Long, medium, short, and
extremely short distance.
The distance-between-vehicles is set to a shorter distance by pressing the CANCEL
switch down. The distance-between-vehicles is set to a longer distance by pressing
the CANCEL switch up.
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The CANCEL switch is pressed one time.The brake pedal is depressed.The selector lever is in the P, N, or R position.
In the following cases, the TJA cancel indication is displayed and a sound is activated
one time.
The DSC has operated.The Smart Brake Support (SBS) has operated.The vehicle is driven on a downslope for a long time.There is a problem with the system.The front radar sensor cannot detect target objects (during rain, fog, snow or other
inclement weather conditions, or when the radiator grille is dirty).
The parking brake is applied.Any of the doors is opened.The driver's seat belt is unfastened.The operation frequency of the braking by the TJA control is high.The parking brake is automatically applied during stop hold control.
Steering assist function
If any of the following conditions occurs, the steering assist function is temporarily
canceled.
The headway control function is canceled.White (yellow) lane lines cannot be detected or a vehicle ahead cannot be
recognized.
Your vehicle speed is more than about 64 km/h (40 mph).The accelerator pedal is operated.The turn signal lever is operated.The vehicle is being driven on a sharp curve.The width of a lane is excessively narrow or wide.The vehicle crosses a lane line.The driver takes his/her hands off the steering wheel.The steering wheel is operated abruptly.There is a problem with the system.The temperature in the Forward Sensing Camera (FSC) is too high or too low.The windshield around the Forwar d Sensing Camera (FSC) is foggy.The windshield around the Forward Se nsing Camera (FSC) is blocked by an
obstruction, causing poor forward visibility.
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If the steering wheel is held lightly, or depending on the road conditions, the
system determines that you have released the steering wheel even if you are
holding it, and an alert is indicated on the multi-information display and the active
driving display.
To resume operation
If the TJA is temporarily canceled, it will resume operation at the previously set speed
by pressing the RES switch after all of the operation conditions have been met.
NOTE
If the set speed is not indicated on the di splay, the system does not operate even if
the RES switch is pressed.
After the operation, the steering assist operation may not operate for a period of 5
seconds at the most until the lane lines are detected or a vehicle ahead is
recognized.
Tu r n i n g off
When the TJA switch is pressed while the TJA is operating, the TJA turns off.
▼Stop Hold Control
While in headway control using the
TJA, your vehicle will stop when a
vehicle ahead stops. When the vehicle
is stopped and the stop hold control
operates, the TJA indicator light turns
on.
NOTE
Even if the TJA is temporarily
canceled during stop hold control,
the vehicle is held in its stopped
position.
The parking brake is automatically
applied and the vehicle is held in its
stopped position when 10 minutes
or longer have passed since the stop
hold control operated. When this
occurs, the TJA is temporarily
canceled.
The brake lights turn on during stop
hold control.
To resume driving
After the vehicle ahead starts moving
while your vehicle is stopped under
stop hold control, press the RES switch
or depress the accelerator pedal to
cancel the stop hold control and start
driving.
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