2014 PORSCHE 911 TURBO brake

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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Driving and Driving Safety 181
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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182 Driving and Driving Safety
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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Driving and Driving Safety 183
When PSM is switched off, PSM support is no longer provided in critical driving situations outside the ABS control range. fPSM should always be switched on during “normal” driving.
However, it may be a good idea to switch off PSM temporarily in exceptional situations:– On a loose surface and in deep snow.– When “rocking the vehicle free”.
Information
The vehicle retains its enhanced braking readiness through prefilling of the brake system even when PSM is switched off.
When PSM is switched off, wheel-specific brake interventions and the anti-slip control system (ASR) are also switched off.The automatic brake differential (ABD) remains on.
Switching PSM back on
fPress button . PSM is active immediately.The indicator light on the button and the PSM OFF warning light on the instrument panel go out.The message “ PSM on” appears on the multi-function display in the instrument panel.
“Sport Plus” mode
A sportier setup is obtained when “ Sport Plus” mode is switched on.PSM interventions occur later than in Normal mode. The vehicle can be maneuvered with greater agility at its performance limits, without having to dispense with the assistance of PSM in emergency situations. This helps to achieve optimal lap times, particularly on race circuits and on a dry road surface.
PSM warning light
– The PSM warning light on the instrument panel lights up for a lamp check when the ignition is switched on.– The light indicates a control operation, even when PSM is switched off, e.g. brake control in the event of one-sided wheel spin.– The light – in conjunction with the multi-function display – indicates a fault.The warning message “ PSM failure Consult a workshop 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.fAdapt your driving style according to the changed conditions.fContact an authorized Porsche dealer.
Towing
For information on towing:fPlease see the chapter “TOWING” on page 278.
No PSM assistanceWARNINGh
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184 Driving and Driving Safety
HOLD function: Drive-Off
Assistant, Standstill Management
The HOLD function, as an assistance function, assists the driver when stopping and driving off on upward slopes.The vehicle is automatically prevented from rolling back away from the desired direction of travel.When the HOLD function is active, the indicator light on the instrument panel comes on.
The vehicle is stopped and prevented from rolling back away from the desired direction of travel even without pressing the brake.
Information
The HOLD function is not available if the PDK selector lever is in position P and N.
If the PDK selector lever is moved while the HOLD function is active, the HOLD function is deactivated.
If the driver’s safety belt is unfastened and the driver’s door is opened while the HOLD function is active, the electric parking brake is activated automatically.
For information on the electric parking brake:fPlease see the chapter “ELECTRIC PARKING BRAKE” on page 151.
The limits set by the physics of driving cannot be overcome, even with the HOLD function. Responsibility for driving off on upward slopes is still the driver’s, despite the HOLD function.Assistance by the HOLD function is not always guaranteed when stopping and driving off on a slippery surface (e.g. on icy or loose surfaces). In this case, the vehicle can slip.fAlways adjust your driving style to the driving conditions and vehicle load. Use the footbrake if necessary.
If the Drive-Off Assistant is not functioning, the driver cannot be assisted when driving off on hills.fHold the vehicle with the footbrake.
If the vehicle comes to a standstill on a steep uphill gradient without operation of the footbrake by the driver, this may result in a certain roll-back before the vehicle is held by the HOLD function. In this situation, the roll-back can be reduced by pressing the footbrake.fAssist holding of the vehicle by increasing the braking force with the footbrake.
Information
When the HOLD function is active, the brake pedal may feel different and you may hear hydraulic noises.
This behavior is normal for the system. It is not a fault.
ABS Brake System
(Anti-lock Brake System)
In spite of the advantages of ABS, 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 ABS.Risk of accidents due to inappropriate speed cannot be reduced by ABS.
ABS helps provide:
– Full steering control The vehicle remains steerable– Good driving stability No skidding due to locked wheels– Optimum braking distance Shorter stopping distance in most cases– Prevention of wheel locking No flat spots on the tires
Limits of HOLD Function
Drive-Off Assistant Not Working
Vehicle Roll-back
WARNINGh
CAUTIONh
CAUTIONh
Loss of control over the vehicleWARNINGh
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Driving and Driving Safety 185
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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Parking 207
ParkAssist
When the driver is parking and maneuvering the vehicle, ParkAssist indicates the distance between the vehicle and a large obstacle by means of signal tones.fOn vehicles with front and rear sensors:For information on the ParkAssist visual display, please refer also to the section “PARKASSIST” in the operating instructions for the Porsche Communication Systems PCM/CDR.
ParkAssist is activated automatically when reverse gear is selected and the ignition is on.
If the vehicle has front ParkAssist, this also issues an automatic warning when the distance between the vehicle and an obstacle in front is less – than approx. 40 in./100 cm (acoustically) and approx. 32 in./80 cm (visually).
A warning signal sounds when – the distance between the vehicle and an obstacle at the rear is less than approx. 71 in./180 cm.The ParkAssist visual display appears on the central screen of the Porsche communication system.
Front and rear ParkAssist is not activated: – At a speed of more than approx. 9 mph (15 km/h).– When the electric parking brake is activated.– When the ParkAssist has been switched off with button A in the overhead console with the ignition switched on. The indicator light in button A lights up.
Responsibility for parking and for assessing the risk to persons, children, pets, and small objects around the vehicle lies completely with the driver. fMake sure that no persons (especially small children), animals or obstacles are within the maneuvering area. fIf the continuous tone sounds, stop and do not move your vehicle further in that direction.
Ultrasound sensors
Sensors
The ultrasound sensors A in the rear bumper and the sensors A in the front bumper (depending on vehicle equipment) measure the distance to the closest obstacle:– Range behind the vehicle: approx. 71 in. (180 cm)– Range at the side of the vehicle: approx. 24 in. (60 cm)– Range in front of the vehicle: approx. 47 in. (120 cm)
Obstacles cannot be detected in the “blind” sensor area (above and below the sensors, e.g. objects hanging down or close to the ground).
ParkAssist LimitsWARNINGh
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