Driving and Driving Safety 175
is suppressed because here, the vehicle does not slow down, despite the engine overrun torque and no fuel is consumed in this driving situation due to utilization of the overrun shut-off.
Ending coasting mode/utilizing engine braking effect
fPress the accelerator or brake pedalor Operate a shift paddle or a shift button or Shift gear using the selector lever.
Initiating coasting mode manually
– Driving in selector lever position D or driving in selector lever position M
When coasting mode is suppressed, e.g. in the case of sporty driving, sudden release of the accelerator pedal or excessively low engine temperature, coasting mode can be initiated manually.fTake your foot off the accelerator pedal and shift past the highest possible gear with the shift paddle, one of the shift buttons, or with the selector lever.
Switching coasting mode on and off using the Auto Start Stop button
Switching off
fPress button . The indicator light on the button lights up.Coasting mode is switched off and automatic stopping of the engine is suppressed.
Switching on
fPress button . The indicator light on the button goes out.Coasting mode is switched on and the engine is automatically stopped when the vehicle stops.
“Sport” mode activated
The PDK transmission switches to a sporty gear- changing map and shortens the shifting times.A sporty driving style is recognized more quickly and the gear-changing speeds are adapted to driving performance.
Braking downshifts are initiated earlier. Downshifts occur for small decelerations, even at higher revs.
“Sport Plus” mode activated
In “Sport Plus” mode, the PDK transmission changes to a shift program designed for driving on race circuits. 7th gear is not selected.The gear-changing performance is enhanced significantly again compared with “Sport” mode.fPlease see the chapter ““SPORT” AND “SPORT PLUS” MODE” on page 188.
Driving off with Launch Control
Launch Control allows you to achieve maximum acceleration from standstill.
Launch Control is designed to be used in a controlled environment on closed circuit driving courses where no vehicle cross traffic or pedestrian traffic is present.fUse Launch Control only if conditions permit it to be applied in a safe manner.fDo not use Launch Control if there is a possibility it could endanger other persons.Such a possibility exists if you cannot see that you have a clear road with no possibility of cross traffic in your intended direction of driving.
Information
Stress on components increases dramatically when starting with maximum acceleration in comparison with normal driving off.
Preconditions: – Launch Control should only be used when the engine has reached operating temperature.–“ Sport Plus” mode must be switched on (indicator light on the button comes on and SPORT PLUS appears on the digital speedometer or on the steering wheel).1. Press the brake with your left foot. 2. Quickly press the accelerator down fully (kickdown activated) and hold it.The engine speed will level off at around 5,500 rpm.“ Launch Control activated” is displayed on the multi-function display.Depending on equipment, the “LAUNCH CONTROL” logo appears on the steering wheel.3. Release the brake within a few seconds.
Remaining stationary for a long time with LAUNCH CONTROL can lead to overloading of the transmission.To protect the transmission, the engine power is then reduced and the LAUNCH CONTROL process is cancelled.
In order to drive off, the accelerator must first be fully released.
Endangering Other Road Users
WARNINGh
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176 Driving and Driving Safety
Shifting gears on the steering wheel
With the shift buttons on the steering wheel, you can change temporarily from automatic selection mode D to manual mode M.
For example: – Shifting down before bends and on entering built-up areas.– Shifting down on downward slopes (engine braking).– Shifting down for brief spurts of acceleration.
The manual selection mode remains engaged: – For cornering (depending on the lateral acceleration) and overrunning.– When the vehicle is stationary (e.g. at a junction).
The system leaves manual selection mode: – automatically after around 6 seconds (unless cornering or overrunning),– after driving off.
Kickdown
The kickdown function is active in selector-lever positions D and M.fFor optimum acceleration, e.g. when overtaking, press the accelerator pedal beyond the full-throttle point (kickdown).
The transmission shifts down depending on the speed of travel and engine speed.Upshifts occur at the highest possible engine speeds.
PDK selector lever
M – Manual selection mode
The currently engaged gear is retained when you change from D to M.
If you change from M to D, the gear-changing map suitable for your current driving style is selected and the appropriate gear is selected.
The selector lever and the two shift buttons in the upper steering wheel spokes or the shift paddles behind these spokes permit comfortable and safe selection of the seven forward gears.
Steering wheel with shift buttons
Shifting up using the selector lever or the shift buttons
fPress the PDK selector lever or shift button on the steering wheel forward.
Shifting down with selector lever or shift buttons
fPull the PDK selector lever or shift button on the steering wheel back.
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Steering wheel with shift paddles
Shifting up with selector lever or right “+” shift paddle
fPress the PDK selector lever forward or pull the right shift paddle on the steering wheel back.
Shifting down with selector lever or left “–” shift paddle
fPull the PDK selector lever or left shift paddle on the steering wheel back.
Shift to N – Neutral using the shift paddles
fPull both shift paddles simultaneously and release them again immediately. Transmission in N – Neutral.
The vehicle rolls with the engine disengaged and at idle speed without engine braking effect. The number in the gear indicator goes out and the selector lever position flashes.
Power transmission can be re-established by pulling one of the shift paddles or by actuating the selector lever.
At low speeds approaching standstill, the brake must be actuated in order to establish power transmission.
Fast gear shifting by repeated operation of the selector lever, shift buttons or shift paddles.
You can shift up or down by the corresponding number of gears by quickly operating the selector lever, the shift buttons or the shift paddles several times in succession.
Gear changes that would exceed the upper or lower engine-speed limit are not executed by the control unit.
There is no automatic upshift at the upper engine- speed limit in selector-lever position M. Upshift suppression can be cancelled by kickdown operation. If, for example, the engine-speed limit is reached during overtaking and an automatic upshift does not occur, the transmission shifts up in this case as a result of kickdown operation.fSelect an appropriately low gear on upward and downward slopes.This will ensure optimum use of engine power and engine braking.
Upshift prompt for fuel-economy- optimized driving
The consumption-oriented upshift indicator A in the tachometer at the right beside the digital speed display helps you to develop a fuel-saving driving style.
The upshift indicator lights up – prompting you to shift up to the next-higher gear – depending on the selected gear, engine speed and accelerator pedal position.fChange to the next-higher gear when the upshift indicator lights up.
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178 Driving and Driving Safety
Limp-home mode
Failure of the selector display in the tachometer
Transm. failure Park vehicle safely
The warning “ Transm. failure Park vehicle safely ” appears on the multi-function display. – Effect: No selector-lever position is displayed in the tachometer.Vehicle can be driven only until it comes to a stop. Action required:It is not possible to continue driving. Stop the vehicle immediately in a suitable place. Have the fault corrected at an authorized Porsche dealer. If the vehicle has to be towed:Please see the chapter “TOWING” on page 278.
If there is a fault in the transmission – Depending on priority, either the “ Transm. failure Park vehicle safely ”, “Transm. fault Poss. no R gear Drive on poss. ” warning or the warning “ Drive temperature too high Reduce load ” will appear on the multi-function display.
Transm. fault Poss. no R gear Drive on poss.
– Effects: Restricted gearshift comfort,reverse gear may not function.Action required:Have the fault corrected immediately at an authorized Porsche dealer.
Transm. failure Park vehicle safely
– Effect: Vehicle can be driven only until it comes to a stop. Action required:It is not possible to continue driving. Stop the vehicle immediately in a suitable place. Have the fault corrected at an authorized Porsche dealer. If the vehicle has to be towed:Please see the chapter “TOWING” on page 278.
Warning “ Drive temperature too high Reduce load ” – Effects:“Warning jerks” can be felt when driving off and the engine power may be restricted.Action required:Do not hold the vehicle with the accelerator on a hill, for example. Hold the vehicle with the brake. Reduce engine load. Stop the vehicle in a suitable place if possible. Allow the engine to run in selector-lever position P or N until the warning disappears.
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Driving and Driving Safety 179
Transmission and Chassis Control Systems
Your Porsche sports car features a complex integrated system made up of all control systems acting in power transmission and in the chassis.
All control systems are networked with the aim of combining the best possible driving performance with maximum safety.
The following systems are involved, depending on equipment:
System/designation Scope
PTM
Porsche Traction Management
– Active allwheel drive with electronically regulated map-controlled multi-plate clutch
PSM
Porsche Stability Management
– Driving stability control – Anti-lock brake system (ABS)– Brake system prefilling– Brake booster (Hydraulic Brake Assist)– Automatic brake differential (ABD)– Anti-slip control (ASR)– Engine drag torque control (MSR)– Steering torque recommendation– HOLD function: Standstill management
PASM
Porsche Active Suspension Management
– Shock absorber system with adaptive, continuous shock absorber control
PDCC
Porsche Dynamic Chassis Control
– Active chassis control system to stabilize roll tendency of vehicle body when driving
PTV Plus
Porsche Torque Vectoring Plus
– Laterally dynamic braking intervention for more agile cornering – Fully-variable electronically controlled rear differential lock
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Porsche Stability Management
(PSM)
PSM is an active control system for stabilization of the vehicle during extreme driving maneuvers.
PSM makes use of both the automatic brake differential (ABD) and anti-slip regulation (ASR) systems, as well as the functions of the anti-lock brake system (ABS) and engine drag torque control system (MSR).
In spite of the advantages of PSM, it is still the driver’s responsibility to adapt his driving style and maneuvers in line with road and weather conditions, as well as the traffic situation.
The increased safety that is provided should not induce you to take greater risks with your safety. The limits set by the physics of driving cannot be overcome, even with PSM.Risk of accidents due to inappropriate speed cannot be reduced by PSM.
Advantages of PSM
– Best possible traction and lane-holding ability in all driving situations – even on road surfaces with varying friction.– The system compensates for undesired vehicle reactions (Ferraria effect) when the driver releases the accelerator pedal or brakes on bends. This compensation functions up to the maximum lateral acceleration.– PSM actively helps to stabilize the vehicle if necessary during dynamic driving maneuvers (e.g. rapid steering movements, during lane changes, or on alternating bends).
– Improved braking stability on bends and on different or varying road surfaces.– Improved brake function and shorter stopping distance in the event of emergency braking.
Readiness for operation
PSM is switched on automatically every time you start the engine.
Function
Sensors at the wheels, brakes, steering system and engine continuously measure:– Speed– Direction of travel (steering angle)– Lateral acceleration– Axial acceleration– Rate of turn about the vertical axis
PSM uses these values to determine the direction of travel desired by the driver.PSM intervenes and corrects the course if the actual direction of motion deviates from the desired course (steering-wheel position):It brakes individual wheels as required. If necessary, PSM also influences the engine power or the gear-changing characteristic of Porsche Doppelkupplung (PDK) in order to stabilize the vehicle.
The events below inform the driver of PSM control operations and warn him to adapt his driving style to the road conditions:– PSM warning light on the instrument panel flashes.– Hydraulic noises can be heard.– The vehicle decelerates and steering-wheel forces are altered as PSM controls the brakes.– Reduced engine power.– The brake pedal pulsates and its position is changed during braking.In order to achieve full vehicle deceleration, foot pressure must be increased after the brake pedal has begun vibrating.
Examples of PSM control operations
– If the “front wheels of the vehicle drift” on a bend, the engine power is reduced and the rear wheel on the inside of the bend is braked if necessary.– If the rear of the vehicle swings out on a bend, the front wheel on the outside of the bend is braked.– Brake system prefilling:The brake system is prepared for possible subsequent emergency braking if the accelerator pedal is released suddenly and quickly. The brake system is prefilled and the brake pads are already applied gently to the brake disks.– Brake booster (Hydraulic Brake Assist):In the event of an emergency braking operation where the pedal force is insufficient, a brake booster provides the braking pressure necessary for maximum deceleration at all 4 wheels.
Loss of control over the vehicleWARNINGh
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Combined operation of PSM and PTV Plus
In order to ensure optimum stabilization of the vehicle, the center differential lock is influenced when PSM interventions occur on vehicles with PTV Plus.
Combined operation of PSM and PTM
In order to ensure optimum stabilization of the vehicle, torque distribution between the front and rear wheels is adapted and the differential lock is influenced when PSM interventions occur on vehicles with PTV Plus.
In the event of a PTM fault, PSM cannot be switched off.If PSM is switched off, it is switched on again automatically.
Automatic brake differential (ABD)
The ABD system controls the front and rear axles separately. If one wheel of an axle starts to spin, it is braked so that the other wheel on the same axle can be driven.
ABD recognizes different driving states, and it features control strategies adapted to these states. In situations in which little propulsive power is required, such as when the vehicle moves off on a level gravel surface, traction control already becomes active at low engine speeds. If a large amount of propulsive power is required, e.g. when driving off on an uphill slope or for rapid acceleration, the ABD system is adapted accordingly.
Anti-slip control (ASR)
The anti-slip control system prevents the wheels from spinning by adjusting the engine power, thereby ensuring good lane-holding ability and stable handling.
Engine drag torque control (MSR)
In conditions of excessive slip, the engine drag torque control system prevents all driven wheels from locking up when the vehicle is overrunning. This is also the case for downshifts on a slippery road.
Steering torque pulse
The steering torque pulse provides the driver with steering assistance when braking on road surfaces with differing friction values.Additional steering forces also assist the driver during counter steering.
Switching off PSM
fPress button for at least 1 second.PSM is switched off after a short delay.The indicator light on the button and the PSM OFF warning light on the instrument panel light up.The warning “ PSM off” appears on the multi-function display in the instrument panel.
When you brake in the ABS control range , the vehicle is stabilized even when PSM is switched off.
One-sided spinning of the wheels is prevented, even with PSM switched off.
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Function
The decisive advantage of ABS lies in the driving stability and maneuverability of the vehicle in hazardous situations.
ABS prevents locking of the wheels during full braking, on almost all road surfaces, until just before the vehicle stops.
ABS begins to control the braking process as soon as a wheel shows a tendency to lock.This controlled braking process is comparable with extremely rapid cadence braking.The pulsating brake pedal and a “juddering noise” warn the driver to adapt his driving speed to the road conditions.fIf full braking is necessary, press the brake pedal fully during the whole braking operation, even though the pedal is pulsating. Do not reduce brake pressure.
Warning light USA
Warning light Canada
If the ABS warning light lights up on the instrument panel while the engine is running, the ABS has switched off because of a fault.The warning message “ ABS/PSM failure Adapted driving permitted ” appears on the multi-function display in the instrument panel.
For information on warning messages on the multi- function display: fPlease see the chapter “OVERVIEW OF WARNING AND INFORMATION MESSAGES” on page 129.
In this case, the braking system will operate without lock prevention , as in vehicles without ABS.fAdapt your driving style to the changed braking behavior.The ABS must be checked by your authorized Porsche dealer in order to prevent the occurrence of further faults with unpredictable consequences.Please contact an authorized Porsche dealer.
The ABS control unit is adjusted for the approved tire dimensions.The use of tires with non-approved dimensions can lead to different wheel speeds, causing ABS to switch off.
Porsche Active Suspension
Management (PASM)
The PASM system actively adjusts the shock absorbers. The adjustable damper system selects the appropriate damping level for each wheel according to the driving situation and driving conditions. Driving safety, agility and comfort are optimized.
Two different chassis setups can be selected at the push of a button:–“ Chassis Normal” –“ Chassis Sport”
In Normal mode the vehicle is in a sporty and comfortable setup.Sport mode offers very sporty shock absorber tuning (e.g. for driving on the race circuit).
In addition to manual mode selection, PASM also adjusts shock absorber tuning for either sporty or comfort driving, depending on the driving situation.
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