Inspection monitorsFree
Before you go to the ITV, look at what the test centre will look at
At the ITV (the Spanish MOT) they plug a machine into the OBD port and check the emissions monitors: the tests your car runs on its own to make sure it isn’t polluting more than it should. Final OBD shows you them first, for free.
- One by oneMisfires, catalytic converter, lambda sensors, EGR, diesel particulate filter and any others your car has.
- Since the last clearKilometres and engine starts since the faults were cleared.
- The warning lightWhether it’s on and how far the car has been driven with it lit.
- FreeIn Free, and no internet needed.
What a monitor is
Tests your car runs on its own
Each monitor is a test the engine control unit runs while you drive: whether the catalytic converter is cleaning properly, whether the lambda sensors respond, whether a cylinder is misfiring. Once it’s done, the monitor shows as complete.
If the faults were cleared recently or the battery was disconnected, the monitors go back to zero and take a few days to complete again. Some, like the diesel particulate filter or the NOx treatment, need long journeys with the engine warm. Final OBD tells you which ones are missing and why, without scaring you.
Buying used
If someone cleared the faults yesterday, you’ll see it here
Under the monitors you’ll see the kilometres and engine starts since the faults were last cleared, and how far the car has gone with the warning light on.
A car with only a few kilometres since the faults were cleared and monitors that aren’t complete is a reason to ask questions. That’s why the monitors are also part of the buy or sell report.
Questions about the monitors
If they all show as complete, will I pass the ITV?
It’s what the test centre checks through the OBD port, but it isn’t the result of the inspection. Still, if they’re complete and the warning light is off, that part is fine. And in the UK, a lit engine warning light is a fail at the MOT too.
How long does a monitor take to complete?
It depends on the monitor and on how you drive. Most complete after a few days of normal use, the diesel ones need long journeys.
Will it work on my car?
On any car with OBD: petrol from 2001 and diesel from 2004 in Europe, and almost every car since.
See inside your car this very afternoon
A cheap OBD adapter, the app on your mobile and five minutes. And if you don’t have an adapter yet, the app comes with a demo of a real car so you can see it all first.
Out now in the stores
