If your dash is showing an AdBlue warning with a mileage countdown, here is the truth of it: the car will keep driving normally until the countdown ends, but once it hits zero and you switch off, it will not restart until the fault is fixed. That is not the garage being dramatic. It is built into the car by law. So no panic, but no ignoring it either. Book in before the countdown does the deciding.
How to check and top up your AdBlue
Video by the RAC. Topping up is a DIY job. If the warning stays on afterwards, that is when you call us.
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This is the classic. If the tank is full and the warning persists, the problem is not AdBlue level. It is the system: a failed NOx sensor, a tired AdBlue pump or injector, crystallised fluid gumming the lines, or a heater fault (AdBlue freezes, so the system has its own heaters). These need proper diagnosis. Our equipment has manufacturer level access to almost every brand, so we can see exactly what the system is complaining about rather than guessing with parts.
The same policy as our DPF page: we do not delete or bypass AdBlue or emissions systems. It is illegal for road use and an MOT failure, a shortcut that turns your car into a liability. The legal fix is nearly always cheaper than people fear, especially caught early in the countdown.
Keep calm and keep driving normally. The car runs fine until the countdown ends. But book in now, not at 50 miles. Once it hits zero and you turn the engine off, it stays off until the fault is fixed.
Either the system needs a proper reset, or there is an actual fault, commonly a NOx sensor, pump or crystallised lines. That is a diagnostic job, and it is exactly what we do.
A urea solution injected into the exhaust to neutralise NOx emissions on modern diesels. The car will not run without a working system, by design, not by accident.
No. Deletes and bypasses are illegal for road use and fail the MOT. We fix the fault instead, and quote before we start.
Absolutely. It is sold at every filling station and it is a DIY job. Just do not put it anywhere except the AdBlue filler (it has happened), and if a warning stays on after a top up, that is when you call us.
Related: DPF: the other diesel warning light · Diagnostics: manufacturer level access to almost every brand · fed up with diesel life? Browse our petrol and hybrid stock
Call 0114 698 1430, send us a message, or book online. Booking only. You can drop the vehicle off outside opening hours by arrangement. Workshop hours: Monday to Friday, 8:30am to 5pm.
Tell us what the car needs and which two days suit you. We come back the same working day to confirm a date.
GT Automotive Group, Unit 3, 1 Orgreave Way, Sheffield S13 9LS. Prices include VAT unless stated.