MAGNETIC RIDE CONTROL
(MRC)
Magnetic Ride Control (MRC), also
known in SI as magneto-rheological real
time damping (MRRTD), independently
controls the fluid viscosity in each of the
four shock absorbers during hard corner-
ing, acceleration, braking and other
dynamic maneuvers.
The driver can select one of two
Magnetic Ride modes: Tour for grand
touring or Sport for performance driving.
Both modes use the same algorithms
but have different calibrations.
A new type of magnetic fluid and a
new piston shape inside the shock allow
the Touring setting to be even softer, and
the Sport setting even firmer.
The CTS-V also has a lower ride height
than the CTS.
BRAKES
The J56 heavy-
duty antilock
brake system
uses Brembo
14.6-in. six-piston
brakes in front and
14.4-in. four-piston
brakes in the rear.
A J63 competi-
tion brake package
uses race-style
front rotors that
are bolted togeth-
er, unlike the regular CTS-V front rotors
which are cast 2-piece rotors. The compe-
tition package also includes red-painted
Brembo brake calipers.
Electric Parking Brake
An electric parking brake is standard on
the 2009 Cadillac CTS-V. An electric park
brake (EPB) release switch replaces the
park brake pedal and release handle used
on the manual system.
The electric park brake module
assembly has an internal motor, apply
actuator, release actuator, and tempera-
ture sensor. The control module also
contains the logic for applying and
releasing the parking brake when
commanded by the parking brake switch.
See the July 2008 issue of
TechLink
for
greater detail.
INTERIOR FEATURES
The instrument panel has a boost
gauge, lateral G meter and added tracers
on the tachometer and speedometer.
The seat inserts are covered in a
suede-like microfiber cover. Metallic
throttle, brake and clutch pedals are also
available with the microfiber package.
Performance Driving Seats
Optional perfor-
mance driving seats
provide excellent
support for spirited
driving. These new,
14-way adjustable
performance seats
include suede seat
inserts and pneumatic
bolster controls in the
seat cushion and
backrest.
A microfiber covered steering wheel
and shifter are optional with the perfor-
mance seat package.
Passenger Presence System
Starting
with the 2009
model year
the CTS-V (and
CTS as well) is
equipped with
a Body Sense
PPS system.
This system
uses input
from a flexible
sensor that emits a low level electric field
to discriminate between an infant in a
child restraint and an occupant sitting
directly on the seat. The Body Sense
PPS system will enable (turn ON) the
passenger frontal airbag for a wider range
of front seat occupants than the system
it replaces.
TIP:
Customers should be aware
that some electronic devices placed on
the front passenger seat (computers,
MP3 players, cell phones, etc.) may
interfere with the electric field generated
by the system, causing it to enable (turn
ON) the passenger airbag and turn on
the safety belt reminder light and chime,
even though the seat is not occupied.
Theelectronic device does not necessarily
need to be turned on to cause this
condition. If this happens, have the
customer remove the electronic device
from the seat.
– Thanks to Toby Davis
3
2009 Pontiac G3 – continued from page 1
– Cast aluminum cylinder head
–DOHC
– 4 valves per cylinder
– Mechanical tappets
– Sequential fuel injectors
Ecotec 1.6L I-4 (LXV) engine
The standard engine for the G3 is the
Ecotec 1.6L I-4 VVT (LXV).
The cylinder block incorporates the
hollow-frame design, reducing the weight
by 17% while maintaining optimized stiff-
ness in the engine-and-transmission unit.
The crankshaft has a new anisotropic
magneto-resistive sensor (AMR) in a
plastic carrier pressed into the cylinder
block. The magnetized sensor disk for the
AMR is located between the crankshaft
and flywheel.
Camshaft phasing optimizes valve
timing over a wide range of engine
operating conditions to improve power
and low end torque output.
The operating efficiency of the 1.6L
Ecotec uses a two step intake manifold.
A rotary sleeve controls the flow of air
through the intake manifold and is
designed to minimize airflow resistance
in the manifold at high speeds.
TRANSMISSIONS
Manual Transmission
The D16 manual 5-speed transmission
(MLM/MM5) is a two-shaft, transverse
design in a one-piece aluminum die cast
housing. It uses a rod-type shifting
system. The final drive ratio is 3.94.
The MLM/MM5 uses a ceramic
hydraulic clutch plate. Shift quality is
enhanced by a shift precision device
(detent pin), and shift effort is reduced by
changing the angle of the 1st/2nd gear
synchronizer.
The G3 has a manual transmission
shift indicator displayed in the instrument
panel as a standard feature (except
Canada).
Automatic Transmission
The Aisin automatic 4-speed transmis-
sion (MLQ/MX0) is an electronically
controlled transaxle, with a torque
converter clutch in an aluminum die cast
housing. The final drive ratio is 3.84.
Reinforcements to the shaft, gear
housing, freewheel, and other areas allow
the MLQ/MX0 to handle a maximum
engine torque of 150 Nm. The 3rd to 4th
shift is clutch-to-clutch, while all other
shifts are one-way clutches.
The TCM includes a cruise up-hill
shift pattern and improvements to the
economic and up-hill shift pattern. The
CAN diagnostic protocols meet OBD II
regulations.
Body Sense Sensor
continued on page 4
