Mon – Fri 9:30am – 5:30pm · Sat 10am – 3pm
Car won't start? Immobiliser light flashing? We diagnose and repair immobiliser faults for all makes without replacing expensive modules.
From
£150
Final quote will be confirmed after vehicle registration and assessment
Estimated 1.5 hrs
Prices shown are starting prices. Final cost depends on your vehicle's make, model, and condition. We always provide a free estimate before starting work.
The vehicle immobiliser is one of the most important electronic security systems in a modern car. Its primary function is to prevent the engine from starting unless the vehicle recognises an authorised key or security credential.
Depending on the vehicle, the immobiliser system can involve the key or transponder, immobiliser antenna, body control module, instrument cluster, gateway, engine ECU and other security-related control units. These systems communicate with each other to verify that the correct key is authorised before allowing the vehicle to start.
When the immobiliser system detects a problem, the vehicle may refuse to start, crank without firing, display a key or security warning symbol, or store immobiliser-related Diagnostic Trouble Codes (DTCs).
At Doyen Auto Services in Dumbarton, we provide professional immobiliser diagnostics and repair for a wide range of vehicle makes and models. Our approach is to identify the actual cause of the immobiliser fault rather than automatically replacing expensive electronic modules.
Common immobiliser-related problems can include:
* Key or transponder programming faults * Lost or corrupted key authorisation * Immobiliser synchronisation problems * Faulty key-recognition systems * Immobiliser antenna faults * Wiring and power-supply problems * Communication faults between security modules * BCM, BDC, FEM or other body-module issues * ECU and immobiliser synchronisation faults * Stored immobiliser DTCs * Software or configuration-related problems * Replacement ECU or module programming issues * All Keys Lost situations
Immobiliser Diagnostics
An immobiliser fault does not necessarily mean the ECU or another major control module has failed.
For example, a vehicle that will not recognise a key could have a problem with the key transponder, antenna, power supply, wiring, communication network or the relevant control module. Simply replacing the ECU without identifying the cause can result in unnecessary expense and may not resolve the original problem.
We use professional diagnostic and programming equipment to assess supported immobiliser systems and determine where the communication or authorisation process is failing.
Where appropriate, diagnostic testing can include:
* Key and transponder identification * Immobiliser system scanning * Security-module fault-code analysis * Live-data assessment * Key-authorisation status checks * Module communication testing * Power and earth checks * Wiring and circuit diagnosis * Immobiliser synchronisation checks * ECU and body-module matching * Replacement-module programming where supported
ECU & Immobiliser Synchronisation
When an ECU or another security-related module has been replaced, the replacement unit may not automatically recognise the vehicle’s existing immobiliser data.
Case-by-case pricing. The figures below are starting “from” prices - your final quote depends on your vehicle's make, model, and condition.
Immobiliser Diagnostic
Immobiliser Repair / Reprogramme
We always provide a free, no-obligation quote before any work begins. Call 07760 926245 or WhatsApp 07760 926245.
Here’s what to expect when you bring your vehicle to Doyen Auto Services
We scan the immobiliser system to identify fault codes and check the communication between key, antenna, and ECU.
The key transponder is tested to confirm it's transmitting correctly and the code matches the ECU.
The specific fault is repaired - whether that's reprogramming a key, replacing an antenna ring, or fixing ECU software.
The complete immobiliser system is verified, and the vehicle is started and tested multiple times to confirm reliability.
We’re a specialist automotive garage in Dumbarton, with the equipment, experience, and honest approach to get the job done right first time.
Specialist immobiliser diagnostic tools that go far beyond standard code readers
We can repair keys, reprogram transponders, and fix ECU immobiliser faults in-house
Honest diagnosis - we'll tell you exactly what's wrong before quoting for a repair
Experienced across a wide range of makes and immobiliser systems
Common questions about this service at Doyen Auto Services
Starting from
£50
Specialist electrical fault finding for complex wiring, sensor, and module issues that other garages can't solve.
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Don't replace what can be repaired. We diagnose and fix faulty engine control units at a fraction of the cost of a new unit.
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£250
Lost all your car keys? We can program new keys and get you back on the road without an expensive dealer visit or vehicle recovery.
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£80
Spare keys programmed for all major makes. Cheaper than the dealer, faster turnaround, and no need to leave your car for days.
Get in touch today to book your immobiliser repair at our Dumbarton workshop. Online booking or call us directly.
Unit 8, Levenside Business Court, Dumbarton G82 3PE · Mon–Fri 9:30am–5:30pm, Sat 10am–3pm
Depending on the vehicle architecture, the module may require coding, configuration, adaptation, synchronisation or transfer of vehicle-specific data before the engine will start.
We can assess compatible replacement modules and determine the appropriate programming or synchronisation procedure.
Key Programming & Immobiliser Faults
A key that previously worked but suddenly stops being recognised can be caused by several different issues. The key itself may be faulty, its programming may have been lost, or the vehicle may have developed a fault in the key-recognition or immobiliser system.
We can diagnose the vehicle and determine whether the issue is with the key, immobiliser system or another related component.
For vehicles where all keys have been lost, we also provide specialist All Keys Lost (AKL) key programming services where technically supported.
Avoiding Unnecessary Module Replacement
A main dealer may recommend replacing a complete control module when an immobiliser fault is detected. While module replacement is sometimes necessary, it is not automatically the correct solution.
Our approach is to diagnose the system first and establish whether the fault can be resolved through programming, synchronisation, electrical repair, key programming or other appropriate intervention.
Where a module has genuinely failed, we can assess replacement and programming options where supported.
Professional Immobiliser Diagnostics in Dumbarton
Immobiliser faults can be frustrating because they can leave an otherwise mechanically healthy vehicle unable to start. Accurate electronic diagnosis is essential because multiple components can produce similar symptoms.
At Doyen Auto Services, we combine advanced diagnostic equipment with module programming and electrical fault-finding capability to identify the cause of immobiliser problems and provide the most appropriate repair solution.
Whether you have an unrecognised key, immobiliser warning light, non-starting vehicle, ECU replacement issue or intermittent security fault, we can assess the vehicle and explain the available options before unnecessary parts are replaced.
Doyen Auto Services Ltd Unit 8, Levenside Business Court, Dumbarton, G82 3PE 0141 467 2904 | 07760 926245
