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Mercedes AdBlue fault repair
An AdBlue warning with a countdown to "no start" needs sorting before the miles run out. We find the failed part — heater, pump or sensor — and fix it. Call us to book in quickly.
Why book with us
Mercedes AdBlue fault repair with clear advice.
Mercedes BlueTEC diesels — including the C-Class, E-Class, GLC, Vito and Sprinter from around 2014 onward — inject AdBlue into the exhaust to cut nitrogen oxide emissions. The system has a tank with a heater, a pump, an injector, and NOx sensors before and after the catalyst to check it is working. If any part fails, the car warns you and starts counting down the miles until it will refuse to restart.
The most common failures we see are the AdBlue tank heater and pump assembly, and the NOx sensors. Crystallised AdBlue can also block the injector or lines. Owners often top the tank up and find the warning stays on, because the fault is with the equipment, not the level. Using contaminated or wrong fluid can damage the system too.
This is not one to leave. Once the countdown reaches zero the engine will not restart after it is switched off, which can mean a recovery truck and a van or car off the road. A failed NOx sensor also leaves the emissions system unable to prove it works, which affects the MOT.
We read the Mercedes AdBlue and engine control units, check the heater and pump operation, test the NOx sensor readings and look for crystallisation at the injector. Then we quote for the part that has actually failed, carry out the repair, and run the system adaptations so the warning clears properly. Call 07498 392333 or book online at our West Bromwich workshop.
Fault found, not guessed
Heater, pump, injector and NOx sensors tested before any part is ordered.
Countdown cleared properly
System adaptations run after repair so the warning goes away for good.
Cars and vans
Book an appointment for BlueTEC cars and Sprinter or Vito vans.
Mercedes AdBlue fault repair
What our Mercedes AdBlue repair includes
Clear expectations, no surprises. If anything extra is needed, we explain it first.
- Fault code and live data read from the SCR and engine control units.
- AdBlue tank heater, pump and level sensor testing.
- NOx sensor readings checked before and after the catalyst.
- Injector and line inspection for AdBlue crystallisation.
- Repair or replacement of the failed part, adaptations run and warning cleared.
Mercedes AdBlue fault repair
Common questions
- I have topped up the AdBlue and the warning is still on — why?
- That usually means a component has failed, most often the tank heater and pump assembly or a NOx sensor. The level was not the problem, so a top-up will not clear it.
- What happens when the countdown reaches zero?
- The engine will keep running, but once it is switched off it will not restart until the fault is fixed. Book in before the count gets low so you are not stranded.
- Can you work on Sprinter and Vito AdBlue faults?
- Yes. The Sprinter and Vito use similar systems, and we are set up for vans with Class 7 MOT testing as well. Call 07498 392333 to arrange a time that suits your work.
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Areas served
Serving drivers across the local area
We provide mercedes adblue fault repair for customers from across the region — book online or call us.
Experts in mercedes adblue fault repair
Tell us your car and symptoms, we will advise honestly.
Serving West Bromwich, West Midlands and surrounding areas towns. Message or call and we will outline likely costs before we book you in.