NOx Sensor Repair

What is a NOx sensor?

The NOx sensor measures the amount of nitrogen oxide that is discharged by a diesel vehicle to ensure that it conforms to specified emissions regulations.

What happens if a NOx sensor fails?

It’s fairly common to have to replace your vehicle’s NOx sensor at some point in its lifetime. Some vehicles are fitted with more than one NOx sensor, at MC Autos we are able to investigate & confirm which NOx sensor has failed or if there is another issue with the emissions system. We are able to replace & where necessary program the replacement NOx sensor.

Signs of a failed NOx sensor that you should look out for are:

  • The engine warning light coming on the dashboard
  • AdBlue system malfunction warning message will display on the instrument panel
  • Your car goes into limp mode
  • AdBlue system countdown message will display ‘no engine start in XXX miles’ (once the mileage reaches 0 the engine will no longer start until the issue is rectified)

Can I drive my car if the NOx sensor has failed?

You might be able to drive for a short time with a faulty NOx sensor, however, once the AdBlue message displays that the engine will not start in XXX miles, once the mileage countdown reaches zero, you will no longer be able to start the engine. The vehicle will also fail its MOT test if any warning lights or messages are displayed regarding the emissions systems.

Can a NOx sensor be repaired?

No, the NOx sensor will need to be replaced with a genuine manufacturer’s part, this sensor has a control unit built into it & most likely will need dealer-level software to carry out the required programming after replacement.

In Croydon, MC Autos provides NOx sensor replacements & we also have the dealer-level software to be able to carry out the required programming.

As a well-established independent garage, MC Autos is proud to be affiliated with several highly respected industry organisations and leading manufacturers. Our IMI accreditation means we have the qualifications to work on highly complex electric and hybrid vehicles. We are delighted to offer Payment Assist (interest-free payment over 4 months), and to be suppliers of Varta vehicle batteries and Shell oils.

To find out more about NOx Sensor Repair in Croydon, call us on 020 8407 3413 or book a reservation online.

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Our Location

Find Us

Unit 3, Stirling Way Industrial Estate
Stirling Way
Croydon
South London
CR0 4XN
020 8407 3413

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Opening Times

Monday 08:30 - 17:30
Tuesday 08:30 - 17:30
Wednesday 08:30 - 17:30
Thursday 08:30 - 17:30
Friday 08:30 - 17:30
Saturday Closed
Sunday Closed

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