Ignition Switch

Control Unit For Ignition Starter Switch.

Fits:
Porsche 987 Boxster 2005>>
Porsche 987 Cayman 2006>>
Porsche 997 MKI & MKII 2005>>
Porsche 997 Turbo/GT2 2007>>
Porsche 997 GT3 2007-11

This product supersedes Porsche's old part numbers:
- 99761815904
- 99761815905

Click 'Zoom in' for large parts diagram.
Diagram ref no 1.

Looking for a reliable replacement ignition switch for your Porsche 997? The Porsche ignition switch (part no. 997 618 159 07) is a genuine OEM part, designed to restore smooth starting and electrical function to your vehicle. Key Features of Porsche Ignition Switch 99761815907 

No Programming Required: This ignition switch is plug-and-play. Simply install and use with your existing key and immobilizer system. 

OEM Quality: Genuine Porsche part ensures perfect fitment, durability, and long-term reliability. Common Fault Fix: Replaces a worn or faulty ignition switch that may cause starting issues, electrical glitches, or accessories failing to power up. 

Updated Design: Supersedes earlier part numbers (such as 99761815900 / 99761815901 / 99761815902) with the latest Porsche-approved version. Vehicle Compatibility The Porsche ignition switch 99761815907 is compatible with: Porsche 911 (997 Carrera, Carrera S, Carrera 4, Turbo, GT2 – various years) Porsche Boxster 987 Porsche Cayman 987 (Always confirm compatibility with your vehicle’s VIN before ordering.) 

Why Choose a Genuine Porsche Ignition Switch? Unlike cheap aftermarket alternatives, this OEM ignition switch guarantees correct operation with your Porsche’s electrical and immobilizer system. No coding or reprogramming is required – install it and your car will start and run normally with your original keys.

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99761815907

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Fibre optic light for ignition/starter switch surround - LHD models. 

Fits:
LHD Vehicles Only

Porsche 981 Boxster 2012-16
Porsche 981 Boxster Spyder 2016
Porsche 981 Cayman 2014-16
Porsche 981 Cayman GT4 2016

Porsche 718 (982) Boxster 2017>> 
Porsche 718 (982) Boxster Spyder 2019>> 
Porsche 718 (982) Cayman 2017>> 
Porsche 718 (982) Cayman GT4 2019>> 

Porsche 991 Carrera 2012-19 
Porsche 991 Turbo/GT2 RS 2014-20 
Porsche 991 GT3/GT3 RS 2014-21

Porsche 95B Macan 2014>>

NOTE: This part is intended for left-hand drive (LHD) vehicles only. If you have a right-hand drive (RHD) vehicle, please order part number 99163213200 instead.

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99163213100

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Ignition / starter switch Historic design.
The ignition starter switch designed with Studio F.A. Porsche Zell am See was milled from a single piece of aluminium and pays homage to historic races.
Note: The historic ignition starter switch can only be used in conjunction with Keyless Go.

Fits:
Porsche 718 (981 / 982) Boxster 2012 >>
Porsche 718C (981C / 982C) Cayman 2012>>
Porsche 991 2012 - 2019
Porsche 958 Cayenne (E2) 2010 - 2017
Porsche 970 Panamera (G1) 2010 - 2016

Porsche - a sports car manufacturer that has "raceborn" in its DNA. The perpetual aspiration of lightweight construction and sporty driving is therefore embedded in every development.

With the historic ignition starter switch, Porsche has developed a homage to historic races and has set itself the task of preserving the Porsche tradition of the "ignition key on the left". It was designed together with Studio F.A. Porsche Zell am See. Visually, it is reminiscent of the historic key head as used in the sports prototypes. For optimum stability and durability, it was milled from a single piece of aluminium. In order to protect the material, but also to recall the silver look of the aluminium bodies from the early days of Porsche motorsport, it was anodised in a clear finish. With 5 holes, finished with a Porsche logo on both sides, the historic ignition starter switch brings a touch of racing history to the Porsche sports cars of today.

Please Note:
The Porsche gift / collection range is subject to availability from the supplier and may take up to anything between 14 - 30 days for delivery if the item is not in stock in our supplier's warehouse

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99104480123

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Ignition starter switch, painted.

Fits:
Porsche 981 Boxster 2013>> (I625)
Porsche 981 Cayman 2014>> (I625)
Porsche 991.1 2012>> (I625)
Porsche 991.2 2016>> (I625)
Porsche Macan 2014>> (I4F2/4F6)
Porsche 958 Cayenne 2011>> (I4F2/4F6)
Porsche Panamera 2010>> (I625)
Porsche 718 (982) Boxster 2016>>
Porsche 718 (982) Cayman 2016>>

I625 - cars with "KESSY" Porsche Entry and Drive
I4F2 - cars with Porsche entry + drive
I4F6 - cars with Porsche entry + drive (usa/can)

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99104480121

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Ignition starter switch.

Fits:
Porsche 986 Boxster 2004>>
Porsche 996 2004>>
Porsche 996 Turbo 2004>>
Porsche 996 GT3 2004>>
Porsche Carrera GT 2004>

Click 'Zoom in' for large parts diagram.
Diagram ref no 22

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4B0905849

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Ignition Starter Switch.

The OE MATCH Ignition Starter Switch is an original equipment-style replacement electrical component designed for selected Porsche Boxster (986), Porsche 911 (996) and Porsche Carrera GT models.

Fits:

• Porsche 986 Boxster 2004>>
• Porsche 996 2004>>
• Porsche 996 Turbo 2004>>
• Porsche 996 GT3 2004>>
• Porsche Carrera GT 2004>

Diagram Ref No 22

Installed as part of the ignition lock assembly, this switch converts the mechanical movement of the ignition key into the electrical switching actions required to activate the vehicle's ignition circuits and initiate engine starting.

The ignition starter switch is an essential part of the vehicle's electrical system. When the driver turns the key, the switch operates the appropriate electrical contacts to supply power to the relevant ignition and accessory circuits and send the starting signal to the starter control system.

A properly functioning ignition switch ensures that the vehicle's electrical systems respond correctly to the selected key position and that the starter motor can be engaged when the driver attempts to start the engine.

The OE MATCH 4B0905849/1 is designed to replace the corresponding original switch, restoring the intended electrical connections and operation without modifying the factory wiring arrangement.

Over time, ignition starter switches can deteriorate due to repeated key operation, electrical contact wear, heat and ageing of internal components.

The electrical contacts may become worn, contaminated or unreliable, resulting in intermittent starting problems, failure of certain electrical accessories or unexpected interruptions to ignition-controlled circuits.

A defective ignition starter switch can cause the engine to fail to crank even when the battery and starter motor are functioning correctly. In some cases, electrical systems may operate inconsistently or lose power when the ignition key is moved between positions.

Replacing a faulty switch with the OE MATCH Ignition Starter Switch 4B0905849/1 helps restore reliable electrical contact, consistent ignition operation and dependable engine starting.

What This Product Does:
The ignition starter switch is the electrical switching component operated by the vehicle's ignition lock mechanism.

Its primary functions include:

• Activates the Ignition Circuits: Supplies electrical power to the appropriate vehicle systems when the ignition is switched on.
• Initiates Engine Starting: Sends the electrical starting signal to the starter control circuit when the key is turned to the start position.
• Controls Accessory Power: Switches the relevant accessory circuits according to the ignition key position.
• Supports Dashboard Electrical Operation: Helps provide the ignition-switched power required by associated instruments and vehicle systems.
• Maintains Correct Key-Position Switching: Ensures the corresponding electrical circuits are activated or deactivated as the key moves between positions.
• Works with the Ignition Lock Assembly: Converts mechanical key movement into electrical switching actions.
• Supports Reliable Engine Starting: Provides the electrical connection needed to initiate the starting sequence.
• Maintains Electrical Circuit Control: Helps distribute power to the appropriate ignition-controlled systems.
• Supports Normal Engine Operation: Maintains electrical supply to relevant ignition-switched circuits while the vehicle is running.
• Preserves Original Equipment Functionality: Restores the factory electrical ignition-switch arrangement.

Symptoms Of Wear Or Failure:
The ignition starter switch is operated every time the vehicle is started or switched off.

Repeated use, electrical loading and age-related deterioration can cause internal contacts or mechanical interfaces to wear.

Common symptoms of a failing ignition starter switch include:

• Engine Fails to Crank: Turning the ignition key to the start position produces no starter motor response.
• Intermittent Starting Problems: The engine starts normally on some occasions but fails to crank on others.
• Key Turns but Nothing Happens: The ignition key moves through its normal positions, but the expected electrical response is absent.
• Repeated Attempts Needed to Start: The driver may need to turn the key several times before the starter circuit responds.
• Loss of Accessory Power: Certain ignition-controlled accessories may fail to operate correctly.
• Intermittent Dashboard Power: Instrument panel warning lights or displays may behave inconsistently when the ignition is switched on.
• Electrical Systems Operating Erratically: Ignition-switched components may turn off unexpectedly or operate intermittently.
• Engine Cutting Out: A severe loss of ignition-switched electrical power may contribute to unexpected engine shutdown.
• Starter Not Engaging Consistently: Worn start-position contacts may interrupt the signal required to operate the starter system.
• Electrical Functions Remaining Active: A switch that fails to change state correctly may leave certain circuits powered when they should be off.
• Unusual Resistance During Key Operation: Damage within the switch or its mechanical drive may affect the feel of the ignition mechanism.
• Intermittent Contact When the Key Is Moved: Electrical systems may briefly activate or deactivate when the key position changes slightly.
• Heat-Damaged Electrical Connections: Overheating or high resistance may cause discolouration or damage around the connector.
• Complete Ignition Switch Failure: The switch may stop supplying power to the expected ignition circuits.

Why Replacement Matters:
Replacing a worn or defective ignition starter switch is important for restoring dependable engine starting and reliable operation of the vehicle's ignition-controlled electrical systems.

• Restores Reliable Engine Starting: Helps correct starting problems caused by defective internal switch contacts.
• Improves Electrical Contact: Replaces worn or unreliable electrical switching components.
• Reduces Intermittent Starting Faults: Helps eliminate inconsistent starter engagement where the switch is responsible.
• Maintains Ignition Circuit Power: Supports continuous power delivery to the relevant ignition-switched systems.
• Restores Accessory Circuit Operation: Helps correct electrical faults caused by defective accessory-position contacts.
• Improves Electrical Reliability: Maintains the intended switching sequence between ignition key positions.
• Reduces the Risk of Unexpected No-Start Conditions: Replaces a deteriorating component before it fails completely.
• Supports Dependable Vehicle Operation: Helps prevent interruptions to ignition-controlled circuits.
• Maintains Factory Wiring Compatibility: Designed for the corresponding original Porsche electrical connection arrangement.
• Original Equipment-Style Fitment: Provides a replacement for the specified factory ignition switch.
• Supports Effective Fault Repair: Allows a diagnosed electrical ignition switch failure to be repaired without replacing unrelated components.
• Ideal for Preventative Maintenance: Suitable when the original switch shows clear evidence of wear or intermittent operation.
• Cost-Effective Replacement: May resolve starting or electrical problems without requiring replacement of the entire ignition lock assembly.
• Supports Porsche Electrical System Maintenance: Helps preserve reliable operation of an important vehicle control system.

The ignition starter switch is a relatively small electrical component, but its operation is essential for normal vehicle use.

A worn switch may initially produce occasional starting difficulties or intermittent accessory faults. As the electrical contacts continue to deteriorate, the problem may become more frequent.

Eventually, the vehicle may fail to crank or certain ignition-switched systems may stop functioning correctly.

Where the switch is responsible for an interruption to ignition power, continued deterioration may also affect the vehicle while it is running.

Replacing a confirmed defective switch with the OE MATCH 4B0905849/1 helps restore the correct electrical switching functions and reduce the likelihood of further ignition-related problems.

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4B0905849

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Ignition starter switch.
Fits: RHD or LHD CARS

VAG Brand

Fits:
Porsche 986 Boxster 1997-04
Porsche 996 upto 2004
*Tip:
If you have a sticky key lock or the key is difficult to get out then replace the steering lock housing, sticking key lock is a very common problem on Porsche 996 and Porsche Boxster 986 models.
Code: 99634701707

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4A0905849B

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Ignition Starter Switch.

The OE MATCH Ignition Starter Switch is a electrical component designed to control the vehicle’s ignition and starter system. Installed behind the ignition lock barrel, the switch transfers the driver’s key input into electrical signals that activate the vehicle’s accessory circuits, ignition system, and starter motor.

Fits:

• Porsche Boxster 986 2.5L 1997-99
• Porsche Boxster 986 2.7L 1999-02
• Porsche Boxster S 986 3.2L 1999-02
• Porsche Boxster 986 2.7L 2003-04
• Porsche Boxster S 986 3.2L 2003-04
• Porsche 996 C2 3.4L 1997-08/01
• Porsche 996 C4 3.4L 1997-08/01
• Porsche 996 C2 3.6L 09/01-2005
• Porsche 996 C4 3.6L 09/01-2005
• Porsche 996 C4S 3.6L 09/01-2005
• Porsche 996 TURBO 2000-05
• Porsche 996 GT2 2001-05
• Porsche 996 GT3 MKI 1999-02
• Porsche 996 GT3 MKII 2003>>
• Porsche 996 GT3 RS 2003-04

Diagram Ref No 22

This OE MATCH ignition starter switch is engineered to provide reliable electrical contact, smooth operation, and direct-fit compatibility with the original wiring system. It plays a vital role in vehicle starting, power distribution, and overall electrical system functionality.

What This Product Does:

• Activates the vehicle ignition system when the key is turned
• Controls power delivery to accessory and ignition circuits
• Engages the starter motor to start the engine
• Distributes electrical power to key vehicle systems
• Works in conjunction with the ignition lock assembly
• Ensures reliable vehicle starting and operation

Symptoms Of Wear Or Failure:

• Engine fails to crank when the key is turned
• Intermittent starting problems
• Loss of power to ignition or accessory circuits
• Dashboard warning lights behaving erratically
• Key turning normally but no starter engagement
• Vehicle stalling due to ignition power interruption
• Electrical accessories failing to operate correctly
• Burnt contacts causing inconsistent electrical connections

Why Replacement Matters:

• Restores dependable engine starting functionality
• Ensures proper power distribution to ignition and accessory systems
• Prevents intermittent starting and electrical faults
• Maintains consistent communication between the key and vehicle systems
• Reduces the risk of unexpected breakdowns
• Supports safe and reliable vehicle operation
• Provides OE-style fitment and performance
• Helps preserve the integrity of the vehicle’s electrical and starting systems

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4A0905849B

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Replacement steering lock housing, sticking key lock is a very common problem on Porsche 996 and Porsche Boxster 986 models.

Ignition Problem Symptoms:
- Car won't start
- Tough to start
- Key gets stuck in ignition
- Key sticking in tumbler

Fits: RHD or LHD CARS

Fits:
Porsche Boxster 986
Porsche 996 upto 2004

Diagram Ref No. 20

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99634701707

The product you are viewing cross references to these numbers

Replacement steering lock housing, sticking key lock is a very common problem on Porsche 996 and Porsche Boxster 986 models.

Ignition Problem Symptoms:
- Car won't start
- Tough to start
- Key gets stuck in ignition
- Key sticking in tumbler

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99634701707

The product you are viewing cross references to these numbers

Ignition Switch Nut.

Fits:
Porsche 987 Boxster MKI 2005>>2008
Porsche 987 Boxster MKII 2009>>2012
Porsche 987 Cayman MKI 2006>>2008
Porsche 987 Cayman MKII 2009>>2012
Porsche 997 Carrera MKI 2005>>2008
Porsche 997 Carrera MKII 2009>>2012
Porsche 997 Turbo / GT2 MKI 2007>>2009
Porsche 997 Turbo / GT2RS MKII 2010>>2013
Porsche 997 GT3.2 2007>>2011

Diagram Ref No 2

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99761875900

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Key head remote control upper part.

Fits:
Porsche 986 Boxster 2001-04
Porsche 996 2002-05 TARGA

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99663735100

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Lock Cylinder. 

The Genuine Porsche Ignition Lock Cylinder (Part Number: 99634791502) is an original equipment ignition and steering lock component designed for selected Porsche 911 (996) and Boxster (986) models.

Fits:

• Porsche Boxster 986 2.5L 1997-99
• Porsche Boxster 986 2.7L 1999-02
• Porsche Boxster S 986 3.2L 1999-02
• Porsche Boxster 986 2.7L 2003-04
• Porsche Boxster S 986 3.2L 2003-04
• Porsche 996 C2 3.4L 1997-08/01
• Porsche 996 C4 3.4L 1997-08/01
• Porsche 996 C2 3.6L 09/01-2005
• Porsche 996 C4 3.6L 09/01-2005
• Porsche 996 C4S 3.6L 09/01-2005
• Porsche 996 TURBO 2000-05
• Porsche 996 GT2 2001-05
• Porsche 996 GT3 MKI 1999-02
• Porsche 996 GT3 MKII 2003>>
• Porsche Carrera GT 2003-06  

Diagram Ref No 21

Manufactured to Porsche's original equipment specifications, this mechanical lock cylinder forms part of the ignition switch and steering lock assembly, providing the key-operated mechanism used to select the vehicle's ignition positions and initiate the starting process.

The ignition lock cylinder is designed to accept the appropriate ignition key and transfer its rotational movement to the associated ignition switch mechanism. It also works with the steering lock assembly to support the vehicle's original locking and security arrangement.

Unlike the electrical ignition starter switch, the lock cylinder is primarily a mechanical component. Its function is to provide the correct key engagement and mechanical operation required to actuate the ignition system.

Over time, the original ignition lock cylinder may develop wear due to repeated key insertion, removal and turning. Internal locking components may become worn, contaminated or damaged, making the key difficult to insert, turn or remove.

A worn or seized lock cylinder can cause starting difficulties, intermittent ignition operation or the inability to operate the ignition key.

Replacing a faulty ignition lock cylinder with a Genuine Porsche component helps restore smooth key operation, reliable mechanical ignition engagement and the original steering lock functionality.

Ideal for ignition lock repairs, steering column maintenance, ignition key problems and Porsche restoration projects, this Genuine Porsche replacement provides a factory-specified solution for compatible vehicles.

What This Product Does:
The ignition lock cylinder is the mechanical key-operated component within the Porsche ignition and steering lock assembly.

Its primary function is to recognise a mechanically compatible key and allow the driver to rotate the ignition mechanism through its designated operating positions.

When the correct key is inserted and turned, the lock cylinder transmits rotational movement to the ignition starter switch, allowing the vehicle's electrical systems and starting circuit to be activated.

The lock cylinder also forms part of the steering lock arrangement, helping ensure the ignition mechanism operates as intended.

Its main functions include:

• Accepting the ignition key: Provides the mechanical key entry and locking mechanism.
• Controlling ignition rotation: Allows the key to turn through the appropriate ignition positions.
• Operating the ignition starter switch: Transfers key movement to the associated electrical switch.
• Supporting engine starting: Enables the mechanical action required to select the starting position.
• Supporting steering lock operation: Works with the steering lock assembly to maintain the intended locking functionality.
• Providing mechanical security: Prevents normal lock rotation when an incompatible key is inserted.
• Maintaining reliable key engagement: Allows the correct key to be inserted, turned and removed as intended.
• Preserving original vehicle functionality: Maintains Porsche's factory ignition lock configuration.

The ignition lock cylinder itself does not generate starter motor power or electronically authorise the immobiliser. Those functions depend on separate electrical and security components.

Symptoms Of Wear Or Failure:
The ignition lock cylinder is subjected to repeated mechanical operation whenever the vehicle is started or switched off.

Over time, internal locking elements, springs and contact surfaces may wear or become contaminated.

Common symptoms of a worn or faulty ignition lock cylinder include:

• Difficulty inserting the ignition key: Worn or damaged internal components may restrict normal key insertion.
• Key difficult to turn: The lock mechanism may become stiff, obstructed or partially seized.
• Ignition key sticking: The key may not move smoothly between ignition positions.
• Difficulty removing the key: Internal wear or incorrect mechanical engagement may prevent easy key removal.
• Intermittent ignition operation: An excessively worn mechanism may not consistently actuate the associated ignition switch.
• Ignition cylinder jamming: Damaged locking components may prevent rotation altogether.
• Excessive movement in the key mechanism: Internal wear may produce an unusually loose or imprecise feel.
• Steering lock release problems: A fault within the ignition or steering lock assembly may prevent normal steering lock disengagement.
• Key requiring repeated attempts: The driver may need to reposition or gently manipulate the key before the cylinder rotates.
• Worn or damaged ignition key: A heavily worn key may interact poorly with the cylinder and produce symptoms similar to internal lock wear.
• Broken key inside the cylinder: A damaged key may fracture and obstruct the locking mechanism.
• Visible damage around the ignition barrel: Signs of forced entry, impact or previous incorrect repairs may indicate lock damage.

Why Replacement Matters:
Replacing a damaged ignition lock cylinder is important for maintaining reliable key operation and the intended function of the Porsche ignition and steering lock assembly.

A worn cylinder may become increasingly difficult to operate and can eventually prevent the ignition key from turning.

If the cylinder seizes completely, the vehicle may become difficult or impossible to start using its normal ignition mechanism.

Installing a Genuine Porsche replacement Ignition Lock Cylinder helps to:

• Restore smooth key operation: Address sticking or binding caused by a confirmed faulty lock cylinder.
• Improve ignition reliability: Restore consistent mechanical engagement with the ignition switch.
• Prevent complete lock seizure: Replace worn internal components before the mechanism becomes inoperable.
• Support reliable engine starting: Ensure the mechanical ignition mechanism can reach the correct starting position.
• Restore normal key removal: Address key retention or removal difficulties caused by cylinder wear.
• Maintain steering lock functionality: Preserve the intended interaction between the ignition cylinder and steering lock assembly.
• Restore mechanical security: Replace damaged or excessively worn locking components.
• Reduce the risk of ignition-related breakdowns: Address developing lock faults before they prevent normal vehicle operation.
• Support ignition system repairs: Provide the correct mechanical component during steering lock or ignition assembly maintenance.
• Preserve original Porsche specifications: Maintain the factory ignition arrangement with a Genuine Porsche replacement.
• Support classic Porsche restoration: Replace deteriorated or damaged ignition hardware while restoring the vehicle.
• Maintain long-term usability: Restore dependable operation of a frequently used vehicle control.

Replacement is particularly recommended when the key consistently sticks, the cylinder becomes difficult to rotate or inspection confirms internal mechanical damage.

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99634791502

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Nut for ignition switch. 


Fits:
Porsche 981 Boxster / Cayman - 2012 to 2016
Porsche 718 Boxster / Cayman - 2017 Onwards
Porsche 991 - 2012 to 2019
Porsche 95B Macan - 2014 to 2018
Porsche 95B Macan - 2019 to 2024
Porsche 970 Panamera - 2010 to 2016
Porsche 958 Cayenne - 2010 to 2017

Click 'Zoom in' for large parts diagram.
Diagram ref no 10


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7PP911094

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Release cable - runs from ignition switch to Tiptronic selector lever, preventing the key from being removed whilst the car is in gear (amongst other functions).

Fits:
Tiptronic transmission only
Porsche 986 Boxster / S 1997-04
Porsche 996 Carrera 1998-05
Porsche 996 Turbo 2001-05

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