Key will not turn or ignition stays asleep
No dashboard wake-up or ignition response.
First checks: both keys, vehicle voltage, fuses, EIS/EZS power, ground, and communication.
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No-start diagnosis before an ignition-module quote
Mercedes Ignition Switch Repair in Dubai
A key that will not turn, a “key not detected” message, or a silent no-crank does not prove the ignition switch has failed. We test the key, vehicle voltage, EIS/EZS authorization, steering lock, wiring, and starter command before recommending repair or replacement.
Initial diagnosis: AED 250–450 including VAT. Compare repair and replacement estimates.
Warehouse 39, Al Quoz 4Mercedes-trained techniciansStar diagnostic equipment
Start with the problem you can see
Four ignition issues that need different tests
Do not buy an electronic ignition switch from the symptom alone. The same no-start complaint can begin at the key, power supply, steering lock, EIS/EZS, starter command, or wiring.
What does the car do?
Choose the closest behavior. If symptoms overlap, the workshop follows the safest and most repeatable one first.
“Key not detected” or intermittent recognition
One key works differently, or the message comes and goes.
First checks: spare-key comparison, reader or antenna response, stored faults, and authorization status.
Steering remains locked
The vehicle may recognize the key but does not release the steering.
First checks: steering-lock status, supply, wiring, mechanical load, and command from the ignition module.
Dashboard wakes up but engine does not crank
Ignition comes on, but the starter remains silent.
First checks: authorization, selector interlock, starter command, relay, wiring, and starter circuit.
Do not repeatedly force the key or steering. If the steering remains locked or the vehicle will not start, ask about recovery or pickup arrangements before moving it.
Services selected by the confirmed fault
Mercedes ignition services available for this job
Each service solves a different failure. The inspection result decides which one belongs on the estimate.
When the ignition system authorizes correctly but the starter does not respond, the job may move to Mercedes starter diagnosis instead of an EIS/EZS repair.
Pricing with inclusions and boundaries
How a Mercedes ignition-switch quote is built
These are planning ranges, not fixed menu prices. Every amount below includes VAT and normal labor for the named work. Your written quote should state the supplied part, setup, exclusions, and timing.
Start hereAED 250–450
Initial ignition and start-authorization assessment, including the relevant scan and first electrical or functional tests.
Call with the exact symptomLocalized key, reader, or circuit repair
For a confirmed local electrical, connector, reader, or key-related issue. Replacement keys and extensive harness work are separate.
Repair the original EIS/EZS
Internal repair where the vehicle’s existing electronic ignition switch is testable and repairable.
Matched exchange or replacement unit
Compatible unit, normal installation, and applicable matching. Unit source and programming requirements are confirmed first.
New vehicle-matched unit
Used when repair or exchange is unsuitable. Parts availability and model-specific setup can move the total above the range.
Separate programming or key work
Quoted only when required and supported by the vehicle, supplied unit, and approved job.
What changes the price
Model, year, unit part number, failure type, module access, repairability, key count, steering-lock involvement, parts source, and programming.
Normally included
VAT and normal labor for the named work. The written estimate identifies the part, installation, applicable setup, and verification.
Quoted separately
Recovery, replacement keys, starter or battery work, steering-lock repair, extensive wiring, liquid damage, and unrelated faults.
Plan for up to one working day
When the fault is present and the vehicle is available, the initial assessment may be completed within a working day. Booking capacity and intermittent symptoms can extend testing.
Confirmed after diagnosis
Local electrical work may be faster than bench repair or a matched replacement. Unit condition, programming, parts sourcing, and steering-lock involvement determine the completion window.
Arrange access before dispatch
Pickup and drop-off are available by arrangement. Share the vehicle location and whether the steering is locked. MercGarage will confirm whether pickup or recovery is suitable, along with timing and any charge.
What we test before removing the module
A scan supports the diagnosis, but it does not finish it
The assessment follows the symptom and model. It can include battery and charging checks, voltage drop, fuse and ground checks, both available keys, module communication, authorization status, steering-lock response, starter command, connectors, and relevant wiring.
If the evidence points inside the EIS/EZS, the original unit can then be assessed for repairability. If the external checks fail, the repair belongs elsewhere in the chain. The related-service links above help you follow the confirmed fault without turning this page into a directory.
Diagnose, decide, verify
How the ignition repair process works
Each stage answers one practical question before the next begins. You approve the repair only after the failed link, price, inclusions, and expected timing are clear.
One start chain, six checks
From the first symptom to a verified start
The key, vehicle power, EIS or EZS, steering lock, wiring, and starter request work together. Testing them in order prevents an expensive module from being replaced on a guess.
Observe
Record what the car does
We note the key response, dashboard behavior, steering-lock condition, intermittent pattern, and recent electrical work.
Establish power
Test keys and voltage
Available keys are compared. Battery voltage, relevant fuses, grounds, and module communication are checked as needed.
Isolate
Follow authorization
Star diagnostic data and physical tests separate the EIS or EZS, steering lock, wiring, interlock, starter command, and starter circuit.
Choose
Compare repair options
We explain whether local circuit repair, original-unit repair, matched exchange, a new unit, or related-system work is supported.
Approve
Review the written estimate
The estimate states VAT, parts, labor, applicable programming, exclusions, timing, and any job-specific warranty terms.
Prove
Verify the completed repair
Final checks cover key recognition, ignition wake-up, steering release, starter operation, rescan, and relevant fault status.
Compatibility is vehicle-specific
Your Mercedes chassis, year, and start system change the repair
EIS, EZS, KEYLESS-GO, start-button, steering-lock, key, and programming requirements are not identical across Mercedes generations. Send the VIN when available so the quote can use the correct fitted system.
What we confirm
The model badge alone is not enough. Vehicle identity and the installed module determine compatibility, repairability, and programming.
Inserted electronic key
We compare both available keys, ignition wake-up, EIS/EZS communication, and steering release where fitted.
KEYLESS-GO or start button
Passive key detection, start request, vehicle voltage, authorization status, and related antenna or reader inputs may need testing.
Separate steering-lock system
A recognized key does not prove the steering lock has released. The ignition module and lock are tested as separate parts of the chain.
Model and chassis differences
C-Class, E-Class, S-Class, GLK, GLC, earlier ML/GL, GLE, and other Mercedes ranges can use different components by chassis and production year.
What you receive
A diagnosis you can use to approve the job
The scope varies with the symptom, but the handover should make the finding, repair choice, price, and remaining uncertainty understandable.
Symptom and key comparison
Exact no-start behavior, messages, intermittent pattern, and both-key result where available.
Relevant scan and live status
Useful faults, communication results, authorization status, and start-request data.
External checks
Applicable battery, voltage, fuse, ground, wiring, connector, steering-lock, or starter-command checks.
Repair recommendation
Local circuit work, original-unit repair, exchange, new unit, key work, steering lock, starter, or more testing.
Written total and exclusions
VAT, supplied part, labor, setup, timing estimate, exclusions, and applicable warranty terms.
Post-work verification
Key recognition, ignition wake-up, steering release where applicable, start function, rescan, and relevant fault recheck.
Benefits tied to the work
What a diagnosis-first repair protects
The goal is not only to make the car start. It is to reduce wrong-part spending, preserve compatible vehicle data where possible, and leave you with a clear repair record.
Test before buying a module
Key, voltage, wiring, steering lock, and starter faults are separated from an internal EIS/EZS failure.
Repair, exchange, or new
The choice follows unit condition, compatibility, data access, and total installed cost.
Know what the quote buys
VAT, supplied part, labor, programming, exclusions, and verification are stated.
Understand what was proven
The recorded symptom, findings, recommendation, and final checks remain understandable after the visit.
Why choose MercGarage
Why choose MercGarage for ignition switch repair?
MercGarage states that its team includes Mercedes-trained technicians and uses Star diagnostic equipment for Mercedes work. The workshop is located at Warehouse 39, Al Quoz 4, Dubai.
The strongest reason to contact the workshop is the combination of vehicle-specific diagnostic capability, repair-first choices, written pricing, and direct access by call or WhatsApp.
Mercedes-trained does not mean manufacturer authorization. Images on this page are AI-generated service images and are not customer-job evidence.
Star diagnostic equipment
Supports Mercedes system scans and status checks. A scan is combined with electrical or physical testing where needed.
Original-unit repair choice
Where supported by testing and unit condition, repairing the original EIS/EZS may avoid unnecessary replacement.
Written estimate boundaries
The quote identifies VAT, parts, labor, applicable setup, exclusions, and the recommended repair path.
Pickup and drop-off
Available by arrangement. Share the location and whether the steering is locked so MercGarage can confirm the suitable transport method, timing, and any charge before dispatch.
Typical estimates for common repair paths
Three Mercedes ignition repair estimates
These planning estimates show how the vehicle, confirmed fault, unit condition, and repair choice can change the total. They are not completed customer jobs or compatibility guarantees.
2015 MERCEDES C-CLASS
Concern: one key is not recognized, while the spare key starts the car normally.
Estimated work: key-side assessment and applicable replacement or setup after the vehicle-side authorization system passes testing.
Condition assumed: EIS/EZS, steering lock, wiring, and vehicle voltage test normally.
2017 MERCEDES E-CLASS
Concern: intermittent key recognition and ignition wake-up with a repeatable internal EIS/EZS fault.
Estimated work: remove, assess, repair, reinstall, and verify the original electronic ignition unit.
Condition assumed: original data remains accessible and the unit is repairable.
2020 MERCEDES GLC
Concern: no ignition authorization after keys, power supply, steering lock, and related wiring pass testing.
Estimated work: compatible matched exchange unit, normal installation, applicable setup, and start verification.
Condition assumed: a suitable exchange unit is available and no separate steering-lock or harness repair is required.
Final price and timing depend on the VIN, fitted unit, failure type, parts availability, data accessibility, and approved work. A written estimate is provided before repair.
Final customer-value check
Before you approve ignition-switch work
Ask for each answer in plain language. This checklist protects you from paying for an EIS/EZS when the key, battery, steering lock, starter, or wiring is responsible.
Was the spare key tested?
If available, its behavior should be recorded.
Was stable vehicle voltage confirmed?
Low supply voltage can disrupt multiple modules.
Which test identified the fault?
Ask which scan result, circuit test, or repeatable behavior supports the recommendation.
Is the original unit repairable?
Understand why repair, exchange, or new replacement is recommended.
What is included in the total?
Part, labor, VAT, programming, key work, and verification should be explicit.
What is excluded?
Recovery, keys, steering lock, starter, battery, and wiring should be clear.
How will the result be proven?
Recognition, ignition, steering release, starting, and rescan where applicable.
What warranty terms apply?
Request any applicable coverage and exclusions in writing.
Ignition and no-start diagnosis in Al Quoz 4
Send what the car does, not just the part name
A dashboard photo and accurate start attempt are more useful than asking for an ignition switch by name. We can confirm the likely inspection path and workshop or pickup arrangements.
Start with three details
- Mercedes model and year
- What happens when you insert the key or press start
- Preferred workshop visit, pickup, or help for a non-starting vehicle
A dashboard message, spare-key result, vehicle location, or VIN can be shared later when it helps diagnosis, access, or parts matching.
If the steering remains locked or the car will not start: confirm recovery or pickup arrangements rather than repeatedly forcing the key or start control.
Mercedes ignition switch FAQs
Clear answers before repair
Short answers for the questions that most often change the test plan, price, or repair choice.
How much does Mercedes ignition switch repair cost in Dubai?
Initial ignition and start-authorization assessment is estimated at AED 250–450 including VAT. Localized key, reader, or circuit work is typically AED 350–950, original EIS/EZS repair AED 850–1,600, and matched replacement work AED 1,600–3,200. New vehicle-matched units can be AED 2,800–4,800 or more. The written quote confirms the fitted unit, labor, setup, exclusions, and final total.
What is a Mercedes EIS or EZS?
EIS and EZS are commonly used names for the electronic ignition switch or authorization module on Mercedes vehicles. Depending on the model, it works with the key, steering lock, engine electronics, and starter authorization. Exact components and terminology vary.
Does “key not detected” mean the ignition switch is bad?
No. The key itself, its battery on applicable functions, the vehicle battery, reader or antenna, wiring, connectors, EIS/EZS, or another authorization component can produce similar symptoms. Compare available keys and test the system before ordering a module.
Can a weak vehicle battery cause ignition problems?
Yes. Low or unstable voltage can prevent modules from waking or communicating correctly. Battery condition, charging voltage where the engine can run, fuses, grounds, and voltage drop may need checking.
Can the original electronic ignition switch be repaired?
Some confirmed internal faults can be repaired while retaining the original unit. Severe damage, liquid entry, inaccessible data, unavailable components, or certain unit designs may require an exchange or new matched unit.
Will a replacement EIS or EZS need programming?
Often some form of matching, personalization, coding, or synchronization is involved, but requirements vary by model, unit, key system, and supplied part. The written quote should state exactly what is required and included.
Can I install a used ignition module?
A used unit may contain vehicle-specific authorization data and may not be directly compatible. Do not buy one from part number alone. Confirm the unit source, matching method, data condition, and full installed cost first.
How long does ignition-switch repair take?
Initial assessment may be completed within a working day when the fault is present. Intermittent faults, module repair, matched-part sourcing, programming, steering-lock involvement, or recovery can extend the time. Timing should be confirmed after diagnosis.
Should I bring both Mercedes keys?
Yes, when available. Comparing both keys can quickly separate a key-specific problem from a vehicle-side recognition or authorization fault.