A TPMS light will fail your warrant of fitness. That’s the part most people find out at the worst moment — the vehicle is otherwise fine, the tyres are fine, and a dash light costs you the WOF.
There’s more than one reason these fail, and what you should do about it depends on which one you’re dealing with.
Two different problems, two different answers
The sensors have simply reached end of life
TPMS sensors contain a battery that isn’t replaceable, and it lasts somewhere between five and ten years. A whole generation of vehicles is now hitting that point at once, which is why this has gone from occasional to routine.
The frustrating part for owners is that they tend to go in sequence. One sensor fails, then a few weeks later another, then a third — because all four were fitted on the same day and have aged identically.
Something happened at a tyre change or puncture repair
This is the other half of what we see, and it turns up across most makes — VW, BMW, Mitsubishi and plenty of others. The sensor sits on the valve stem inside the wheel, and it’s easy to damage when a tyre is being removed or refitted.
If your light came on shortly after a tyre change or a puncture repair, that’s very likely your cause rather than a coincidence. It’s usually one sensor rather than four, and replacing it is the obvious answer.
Where we see this most
Ford and Mazda dominate what comes through our workshops, particularly the Ranger and the BT-50. Worth being honest about that: it partly reflects how many of these are parked in West Auckland rather than any judgement about the brands. Volume shapes what a workshop notices.
| Model and years | System | What you’ll see |
|---|---|---|
| Ford Ranger PX / PX2 / PX3, approx. 2014–2023 | Direct, mainly 433 MHz | Dead or intermittent wheel sensors, increasingly common with age |
| Mazda BT-50, approx. 2011–2019 | Direct 433 MHz | The same age-related failures, on closely related hardware |
| Ford Kuga 2014–2019 | Direct 433 MHz | Sensors dropping out intermittently before failing outright |
| Ford Focus, approx. 2014–2019 | Direct 433 MHz | Dead batteries, sensor not detected, relearn problems |
| Ford Mondeo, approx. 2014–2020 | Direct 433 MHz | Battery failure, clamp-in and snap-in depending on year |
| Ford Mustang 2015 on | Direct 433 MHz | Same sensor ageing, fewer through the workshop |
| Mazda CX-5 approx. 2017 on | Direct on many versions | Now entering the age where sensors fail |
| Mazda CX-3 approx. 2018 on | Direct on many versions | Beginning to appear |
| Mazda CX-9 approx. 2013–2016 and later | Direct | Battery and sensor failures, lower volume |
What it means for your WOF
NZTA is unambiguous. A vehicle fails its warrant if a TPMS warning is active — a lamp illuminated or a message on the dash. Where a sensor has been removed, or the factory wheels replaced, the requirement is that the sensor is replaced or the dash light is disabled.
We carry out warrant of fitness inspections at both workshops, so we can sort the sensor and the WOF in one visit.
Both routes are legitimate. Driving around with the light on is the only option that isn’t.
Your options
Replace the sensors
Genuine sensors are expensive. We fit aftermarket sensors, program them and carry out the relearn, using our Launch equipment and a dedicated TPMS programming tool. We do this across most makes, not just Ford and Mazda.
This is the right answer when one sensor has been damaged, and it’s the right answer if you want the system working. You keep a genuine safety feature that tells you about a slow leak before it becomes a problem.
Delete the system — Ford and Mazda only
On Ford and Mazda we can disable TPMS properly using FORScan, coding it out rather than masking it. It’s permanent: it won’t return on its own, and it would take FORScan or a factory tool to switch back on.
If you run fleet or commercial vehicles, this is worth planning for rather than meeting one WOF at a time. We can check sensor health across your vehicles at their next service.
Where this makes sense is an ageing high-kilometre vehicle, particularly a commercial one, facing four sensors at once on a vehicle whose remaining life doesn’t justify the spend.
We can’t offer this on other makes. FORScan is a Ford and Mazda platform, and we’re not going to claim capability we don’t have.
Worth thinking about before you delete
We’ll do it, and for the right vehicle it’s a sensible commercial decision. But it’s worth saying plainly what you’re giving up.
TPMS earns its keep most on exactly the vehicles people most want to delete it from. A private owner notices a soft tyre. A work ute with three drivers who each have it for a few days, nobody owning it, nobody checking pressures with a gauge — that’s where a slow leak runs for weeks, and that’s where it ends in a ruined tyre or a blowout on the motorway.
Deleting removes the warning. It doesn’t fix the tyre. If you go that route, put manual pressure checks into your routine, and we’ll check pressures at every service as a matter of course.
Common questions
Will a TPMS light fail my WOF?
Yes. An active TPMS warning is a fail. Either the sensor gets replaced or the light gets disabled — both are acceptable to NZTA.
Can you delete TPMS on my Toyota or VW?
No. We do the delete on Ford and Mazda, through FORScan. On other makes we replace and program sensors instead.
My light came on right after a tyre change. Is that related?
Very likely. The sensor sits inside the wheel on the valve stem and is easily damaged during a tyre change or puncture repair. That’s usually one sensor rather than a system-wide failure.
Do I have to use genuine sensors?
No. Genuine sensors are expensive and aftermarket ones work properly once programmed and relearned correctly.
Can a delete be undone?
Yes, with FORScan or a factory tool. It won’t come back by itself, but it isn’t irreversible if you sell the vehicle and the new owner wants the system running.
Run this vehicle for work? See our fleet servicing page — we look after vans, utes and company vehicles across West Auckland from our Henderson and Avondale workshops.
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