How To Fix Hyundai “Low Tire Pressure” Warning/TPMS Error

The other day I blogged about an issue I was having with my i30N with a persistent, seemingly erroneous, TPMS error/”low tire pressure” warning.

In this article I want to explain how I fixed the problem (without needing to go back to the dealer).

Research has indicated that MANY owners of Hyundai vehicles – not just the i30N, but more ‘mainstream’ models e.g. Tucson, Santa Fe, Kona etc – have the same issue.

I figured this could be a helpful, simple, resource for anybody with a Hyundai facing the same error.

Recapping The Problem

Long story short, what happens is that the “low tire pressure” warning illuminates on the dashboard, drawing your attention via this warning light (NB this is not from my i30N but another Hyundai, I foolishly forgot to take any photos of the error I was having)

And also an additional graphic in the dash display that shows the “offending” tire(s) with the current pressure.

From what I understand, the error often occurs when the temperature drops a bit – this is what happened to me.

Filling the tire with air doesn’t seem to immediately solve the problem.

Why Does It Occur?

It seems that Hyundai’s Tire Pressure Monitoring System (TPMS) is very sensitive.

If pressures aren’t right, it throws a wobbly. However, despite being “quick to anger” in terms of showing you a low pressure it is then very slow to actually clear this error.

Because very few modern Hyundai cars have a manual reset/override option, you have to convince the TPMS that the pressure is right. This can be more challenging than you think, as you might be using the wrong pressure setting (more on that below) for the TPMS.

How To Fix It?

The process is meant to be as follows:

• Put air in the tire with the warning
• Drive for a bit – ideally at motorway speed
• The warning light should go off

I tried all this, and it didn’t work.

Here’s how I fixed the problem.

Firstly, ignore whatever your car dealer, mechanic, or tire shop might have written on a wheel alignment sticker with respect to correct pressure, or whatever you’ve read online about the correct pressure for the tires (NB I’m not sure if this is a common thing outside of New Zealand, but here it is very common for tire shops to place a little sticker in the windscreen that displays the next due wheel alignment date/mileage and also the recommended tire pressures).

Instead, you need to find the Hyundai recommended tire pressures for your car, which are usually on a sticker on the inside of the driver’s door. E.g. on my car the sticker is here:

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This reveals the correct tire pressures (as I have XYZ tires) as being 39 PSI at the front and 36 PSI at the rear. I’m using PSI here as that’s what we use in NZ, but the same rule applies if you use bar or whatever the measurement system is in the USA or other markets.

As you can see, this is very different to what the Hyundai dealer recommended:

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In the first instance I had been inflating to 34/34. This didn’t clear the error. I also tried inflating the fronts to 36 PSI and rears to 34 and that didn’t work either. As a side note, I’m surprised the car didn’t throw an error earlier as I had been driving it on 34/34 as recommended by the dealer, but when the temperature dropped here a bit the tires showed 32 PSI all around and this is when the warning came on.

When I had this error I actually had two warnings – one for each front tire. It was then I had the idea that the TPMS system will probably be set to whatever Hyundai has written on the tire pressure card, not whatever the tire shop recommends (I mean obviously, right?)

As I was getting warnings on the front tires only, I inflated them both to 39 PSI.

No luck, I still had the errors, even after driving.

I then thought “why not inflate the rear tires to 36 just in case?”. So I went back to the petrol station, selected 39 PSI on the fronts, and then 36 PSI on the rears.

Lo and behold, the warnings disappeared immediately after ALL tires were inflated to the recommended pressures.

So with that in mind, here’s an abridged process:

1. Find the ‘tire pressure card’ in your Hyundai (e.g. in the door, might also be in the manual) – ignore any other recommended pressures
2. Inflate ALL tires when COLD to the recommended pressures. Do not just inflate the problematic tire. For me this was the ‘magic step’ that actually fixed the problem. It wasn’t until I had inflated the rears (that showed no errors) to thei recommended pressures that the warnings for the front tires disappeared.
3. If this doesn’t clear immediately, drive for a bit and then see if that works.
4. If you’re still having an issue, inflate each tire 1-2 PSI above the recommended figure. Drive for a bit if needed. I didn’t need to do this, but others have recommended slightly over-inflating to fix the issue.
5. If that works, then you can let the air out back to the recommended PSI/pressure.

If these steps didn’t work, then chances are that one of the sensors is defective and you’ll need to get your dealer or a trusted third party mechanic to sort the issue.

I think a lot of the issues seem to stem from a combo of the sensors being overly-sensitive, and also people using the wrong pressures (because they are going off what the tire shop/dealer has recommended, or what they have read online). You MUST use the Hyundai recommended pressure that is supplied with the car, or else you probably won’t be able to fix the problem.