OVERVIEW
Though performance and drivability were the focal points during
the development of the new CL coupe, these characteristics should
never be at the expense of safety, security and accident avoidance.
The CL is engineered as a total safety package with features designed
to help in collision avoidance and to enhance the safety of the
passengers in the event a collision is unavoidable.
Featured as standard equipment on the Type S, the Acura Vehicle Stability Assist (VSA) system combines the Traction Control System (TCS) and Anti-lock Brake System (ABS), and synchronizes these two elements to assist in enhancing driver control of the vehicle during sudden collision-avoidance maneuvers. Other safety items in the area of avoidance include Xenon / High Intensity Discharge (HID) headlights and the center high-mounted stop light.
Should a collision prove unavoidable, the CL protects its occupants with a computer-designed safety structure with front and rear crumple zones, and side impact intrusion counter-devices help protect the passenger compartment. To supplement the structural engineering in the body, the CL features standard driver and front passenger Supplemental Restraint System (SRS) dual-threshold air bags with a dual-stage passenger air bag, seatbelt pretensioners with load-limiters, and an advanced side air bag system.
VEHICLE STABILITY ASSIST (VSA) SYSTEM
First equipped in the 2000 model year Acura 3.5 RL flagship sedan,
the Acura Vehicle Stability Assist (VSA) system is standard equipment
on the 3.2 CL Type S model. Similar to the 3.5 RL system, the CL's
VSA system orchestrates the throttle and brakes to seamlessly
integrate traction control, anti-lock braking and stability
enhancement processes. This innovation is designed to assist the
driver in maintaining control during acceleration, cornering and
sudden collision-avoidance maneuvers by applying braking force to the
right or left front wheel as necessary and managing the throttle
system.
By monitoring input from eight vehicle sensors, the VSA system can calculate a predicted range of vehicle response while constantly monitoring the vehicle's actual response and the driver's control inputs. If the actual response is outside the predicted response range -- as when cornering forces exceed the tires performance, for example -- VSA automatically intervenes with corrective action. In the case of oversteer (which may lead to spin), VSA applies braking to the outside front wheel to counter the unintended yawing tendency. On the other hand, if understeer becomes pronounced, VSA applies braking to the inside front wheel and reduces engine power to turn the car back into the intended course.
Unlike some vehicle stability systems, which can seem intrusive to enthusiast drivers, the Acura VSA is calibrated to add to stability and predictability, without stifling the driving enjoyment of the CL's carefully engineered chassis and double wishbone suspension. An indicator light flashes on the instrument panel while the system is actively enhancing the stability of the vehicle. A cockpit switch is provided to disable the VSA and TCS while leaving the antilock braking system fully functional.
ANTI-LOCK BRAKING SYSTEM (ABS)
The CL's standard 4-wheel Anti-Lock Braking System (ABS) enhances
steering control during hard braking. Speed sensors at each wheel
send signals to the ABS control module. When the system detects
impending wheel lockup, it first holds, then reduces hydraulic
pressure to the affected wheel, letting it regain traction before
full braking resumes. The ABS function is also highly effective on
split-friction surfaces, in which one side of the vehicle has
significantly less traction than the other.
While the 3.2 CL features a three-channel ABS system, the Type S is fitted with a special four-channel system that works in conjunction with the VSA system. Both ABS systems operate in three-channel mode during straight-line braking, apportioning braking power to the front wheels independently and the rear wheels in tandem. This enhances the driver's ability to maintain steering control during panic stops on slick road surfaces.
The Type S ABS system automatically switches to a four-channel mode when the system senses high cornering forces. This allows the ABS system to take advantage of weight transfer to the outside of the turn during cornering and apply higher brake pressure to the outer rear wheel for enhanced braking performance.
TRACTION CONTROL SYSTEM (TCS)
The standard equipment Traction Control System (TCS) on the CL
coupe detects wheel slip under acceleration and coordinates use of
braking and ignition retard to regain traction. For the Type S, TCS
utilizes sub throttle and ignition retard as well as front braking
and fuel cut.
In situations where the front drive wheels are on different friction surface, such as when one drive wheel is in water while the other is on dry pavement, the system applies braking action to the wheel that's slipping, allowing the tire with better grip to move the vehicle. In addition, the system also reduces total engine power output to minimize wheelspin.
SAFETY STRUCTURE
The CL's passenger "safety cage" was engineered from the earliest
stages of development to meet tough safety regulations. Using
computers to conduct extensive crash simulations, engineers studied
the impact forces on a "virtual car" to supplement actual prototype
crash testing. These tests led to the development of numerous safety
innovations in the design of the CL.
In frontal impacts, straight-section frame box rails with large cross-sections feed impact energy directly into the main frame structure. To meet new 2002 federal head-impact safety regulations, the CL's interior has energy absorbing roof-pillar garnishes and roof lining designed to help reduce injury to the occupants. To better deal with offset-impact energy, reinforcements are placed at the roof side rails, floor frame, A-pillars and front and side frame members.
SIDE IMPACT PROTECTION
Extensive reinforcements were made to the CL's structure to help
protect occupants during side impacts. The B-pillar thickness was
increased and stiffened to minimize the possibility of intrusion
during a side impact while a substantial cross member runs
transversely across the floor pan to reinforce the passenger cabin
structure. The doors have special twin-side impact reinforcement
beams as well as impact-absorbing door-lining pads.
DUAL SUPPLEMENTAL RESTRAINT SYSTEM (SRS) AIR BAG
The CL is equipped with a driver's and front passenger's air bag
Supplemental Restraint System (SRS). The driver's air bag is located
in the steering wheel hub, while the passenger's air bag is located
on top of the dash. To ensure maximum reliability, the sensors use
gold-plated electrical connectors. As in all Acura automobiles, the
front passenger air bag is designed to deploy upward along the
windshield and then back toward the occupant. This provides a large
cushion to help protect the front passenger.
DUAL-THRESHOLD AIR BAGS
To further enhance the operation of the sophisticated SRS system,
a sensor detects whether the driver's and front passenger's seat
belts are fastened. The dual-threshold system uses this information
to determine how much impact force will be required to make the bag
deploy. If either front seat occupant is unbuckled, their respective
air bag will deploy at a lower impact force collision to help protect
the unbelted occupant. Conversely, if the seat occupants are buckled,
their respective air bag will require a larger impact to activate the
bags.
DUAL-STAGE PASSENGER AIR BAG
To enhance the protection of the front seat passenger during a
variety of frontal impact collisions, varying air bag deployment
speed is used in the CL. This exclusive system designed specifically
for Acura uses a dual-stage inflator, and automatically adjusts the
deployment of the front passenger SRS air bag based on the severity
of the crash. During a slower speed collision, the dual-stage
inflator system for the dash-mounted air bag is triggered in
sequence, resulting in slower overall air bag deployment with less
initial force. During a higher speed collision, both inflators
operate simultaneously for full immediate inflation, to correspond
with the greater impact force.
FRONT SEATBELT PRETENSIONER WITH LOAD-LIMITER
The CL is equipped with standard driver and front passenger
seatbelt pretensioners. A pyrotechnic device is utilized in the
seatbelt retractor mechanism, which tightens the seatbelt in the
event of a collision. This feature assists in keeping the occupant
firmly in the seat during the initial collision, further enhancing
the effectiveness of the seatbelts. The pretensioner works in
conjunction with a load-limiter, which reduces forces on the occupant
during a frontal collision.
ADVANCED SIDE AIR BAG SYSTEM
Likes its RL and TL siblings, the new CL features an
Acura-exclusive, seat-mounted advanced side air bag system for the
driver and front seat passenger. The front passenger seat is equipped
with an innovative occupant position detection system designed to
disable side air bag deployment and prevent injury to a small child
(or small adult) if they lean their head into the side air bag
deployment path. A series of seven sensors in the passenger seatback
determine the size and position of the occupant to determine if it is
safe to deploy the side air bag. If the child is in the deployment
path of the side air bag, the system will disable the side air bag
from inflating. If the child returns to an upright seating position,
the side airbag will reactivate so it can deploy and protect the
child in a side impact.
HIGH INTENSITY DISCHARGE (HID) HEADLIGHTS
Typically an extra-cost option, if offered at all on competitive
cars, the CL follows the RL and TL sedans' lead and is equipped with
standard reflector-type xenon/High Intensity Discharge (HID) low beam
headlights. Three times as efficient as conventional halogen lamps,
the Acura HID system uses less energy, with more than double the bulb
life. The useful range of illumination on low beam increases by 39
percent and the increased beam width eliminates the need for separate
fog lights. The CL's high beams use conventional halogen bulbs and
operate in conjunction with HID. An auto-off feature turns off the
headlights 15 seconds after the driver's door is closed or the doors
are locked.
ANTI-THEFT ALARM SYSTEM
The CL is equipped with a standard keyless-remote entry feature,
which locks and unlocks the doors and opens the trunk at the push of
a button. The key fob also operates the standard security system on
the CL. When an unauthorized attempt is made to enter or start the
vehicle, the horn sounds, the flashers are activated and the starter
system is disabled. The system automatically arms itself after the
doors are locked and is disarmed when a door is unlocked with the
keyless-remote fob or with the door key. The alarm can also be
activated by depressing the "panic" button on the remote-keyless
fob.
SECURITY/IMMOBILZER SYSTEM
The key for the CL is imbedded with an electronic microprocessor
unit that prevents the car from being started, even if a mechanical
duplicate of the proper key shape is used. A transponder built into
the key signals the immobilizer control unit that the key is genuine.
If hot-wiring is attempted, or an unauthorized key is used, the car
simply will not start.