Activity Key

Short description: JLRCoding supplies a factory‑spec Activity Key, carries out vulcanised bonding to the door‑handle sensor, programs the Central Electronic Module (CEM) and validates waterproof performance – all for £249 + VAT.

Technical Overview

The Activity Key is a low‑frequency (125 kHz) RFID strap that replaces the traditional key‑fob on the Defender L663 series. It is permanently bonded to the Door‑Handle Proximity Sensor (DLS) using a high‑temperature vulcanisation adhesive, creating a sealed joint that can survive immersion to 10 m for 10 minutes without loss of signal. The DLS transmits the key’s ID to the Central Electronic Module (CEM), which controls lock, unlock and start‑engine functions.

Because the key is welded to the DLS, it never separates from the vehicle, eliminating the risk of loss while providing true keyless convenience. Activation requires three core actions:

• Vulcanisation of the new RFID strap to the DLS housing.
• Programming the CEM with the unique key ID (JLR TechTool).
• Water‑tightness verification and on‑road functional testing.

Key components (original JLR part numbers)

Component	Part No.	Specification
Activity Key (RFID strap)	8U1100	125 kHz, 10 m sub‑mersion, 30‑day battery
Door‑Handle Proximity Sensor (DLS)	8U1105	0‑200 mm detection range, 1 % accuracy
Central Electronic Module (CEM)	8U1110	Firmware ≥ 5.04, stores up to 32 key IDs
Vulcanisation adhesive	8U1115	2‑hour cure, 150 °C max, 1000 h weather rating
Backup RFID fob (optional)	8U1100‑B	433 MHz, 12 V battery

Why Choose an Activity Key?

Four practical advantages make the Activity Key the preferred solution for Defender owners who demand off‑road reliability:

1. True keyless operation: The vehicle unlocks, locks and starts automatically when the key is within 200 mm of the DLS – no need to press a button or pull a fob.
2. Water‑proof construction: The vulcanised joint is certified to 10 m depth, so the key survives river crossings, beach drives and weather exposure.
3. Permanent mounting: Because the strap is bonded directly to the door‑handle, it cannot be misplaced or torn off.
4. OEM‑level security: The CEM encrypts the key ID using JLR’s proprietary algorithm, ensuring that only the programmed key can access the vehicle.

Eligibility & Pre‑Fit Inspection

The service is limited to Defender L663 MY24‑25 models that already have the DLS hardware fitted (or a factory‑fit retrofit kit). Before booking, the workshop must confirm:

• VIN shows a 2024‑2025 build (year code “X” or “Y”).
• CEM part number is 8U1110 with firmware version ≥ 5.04.
• DLS sensor is intact, correctly mounted, and free of corrosion.
• All CAN‑bus connectors are secure.
• No active DTCs on the proximity‑sensor CAN channel after a quick OBD scan.

If the DLS sensor is missing or damaged, we can supply a complete retrofit kit (sensor + Activity Key) as an add‑on.

Replacement & Activation – Step‑by‑Step Procedure

1. Power isolation: Disconnect the 12 V battery and wait ≥ 5 minutes to discharge residual CAN energy.
2. Remove old strap (if present): Apply a heat gun to raise the adhesive temperature to ~150 °C, gently pry the existing strap away, and clean the residual adhesive with isopropyl alcohol.
3. Inspect DLS sensor: Verify the sensor’s wiring harness, connector pins, and mounting hardware for damage.
4. Bond new Activity Key: Apply the vulcanisation adhesive (part 8U1115) to the RFID strap, position it precisely on the DLS housing, and cure for 2 hours at 150 °C.
5. Diagnostic connection: Re‑attach the battery, plug a JLR TechTool cable into the OBD‑II port, and open the “Central Electronics” module.
6. Firmware check: Confirm CEM firmware ≥ 5.04; if older, flash the latest version (v5.06) via TechTool → Update → Central Electronics.
7. Program the key: In TechTool → Vehicle Setup → Activity Key select “Add New Key”, scan the freshly bonded RFID strap and store the ID (v1.2 map).
8. Waterproof test: Submerge the bonded key in a pressurised water bath at 10 m depth for 10 minutes. After removal, verify that the CEM still recognises the key (no DTCs).
9. On‑road functional test: Perform a short drive on a closed‑track:
   • Approach the vehicle with the key within 200 mm – doors should unlock automatically.
   • Press the start button – engine should fire without holding a fob.
   • Walk away – doors should relock automatically after 30 seconds.
10. Documentation: Generate a PDF Activation Report (VIN, timestamps, CEM firmware, adhesive cure data, waterproof test results) and provide the owner with a printed “Activity Key Replacement Certificate”.

Advantages for Workshops & Fleet Operators

• Revenue potential: Standard price £249 + VAT, inclusive of parts, labour, diagnostics and certification.
• Streamlined workflow: Identical steps for every eligible Defender reduce training overhead.
• Compliance: The upgrade meets ECE R10 type‑approval for keyless‑entry systems.
• Customer loyalty: Supplying a genuine JLR Activity Key positions your centre as a premium‑service provider.

Pricing & Ordering Details

Our all‑inclusive package contains:

• OEM Activity Key (part 8U1100) and vulcanisation adhesive (8U1115).
• Full diagnostic session with JLR TechTool.
• CEM firmware update and key‑ID programming.
• Waterproof sub‑mersion test (10 m for 10 minutes).
• On‑road functional verification (unlock, start, lock).
• Electronic activation report and printed certificate.
• 12‑month warranty covering parts, labour and software.

Standard price: £249 + VAT. If the CEM firmware is older than 5.04, a firmware‑only update is available for £129 + VAT.

To order, fill out the JLRCoding contact form, select “Defender – Activity Key Replacement & Activation”, and attach a copy of the vehicle’s service history or VIN verification.

Frequently Asked Questions (FAQ)

Do I need to replace the DLS sensor?

No – the existing DLS sensor is retained. Only the RFID strap is replaced and re‑bonded.

Can the Activity Key be removed later?

Yes. Applying heat to the adhesive softens the bond, allowing the strap to be peeled off. The vehicle will then revert to standard key‑fob operation.

Is there a warranty?

Yes – a 12‑month warranty covers bonding failures, coding errors and waterproof‑test issues. OEM components remain under JLR’s standard parts warranty.

Will the upgrade affect my insurance?

Most insurers view the Activity Key as a convenience upgrade and do not change premiums, but you may wish to notify your provider.

Contact JLRCoding Support

Email: support@sx-tool.com

Address: 12 Cedar Road, London SW1 5AB, United Kingdom

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Blog page description: Complete guide to replacing and activating the Activity Key on a Land Rover Defender. Includes hardware checklist, JLR TechTool coding, vulcanisation bonding, waterproof test and on‑road validation.

Blog page tags: Activity Key, Defender Activity Key, JLR Activity Key coding, waterproof key, keyless entry, DLS sensor, Land Rover Defender, JLRCoding