Tyre Pressure Monitoring

[Guest001]

OK so I have tried over filling the tyres and holding down the button and yelling at it but nothing has worked so far.

How do you go about replacing the batteries?

I don't suppose this issue would be covered by Allianz Extended Warranty? I haven't had to use them for any claims so far...

Probably have to strip the tyres and change battery and replace and balance. $30 per corner perhaps. Mine use Li ion batteries which were supposed to last a long time but didn't always so I bought a packet of them off Ebay which were much cheaper.

[Diesel_vert]

My R36 is complaining to me to "check tyre pressure". I have checked and sure enough it's fine. I'm guessing one of the sensors have died - is there a way that I can check to see which one is returning a faulty value?

If the vehicle uses a direct TPMS (i.e. fitted with individual TPMS sensors), then it's usually possible to identify which tyre or sensor is causing the alert through the vehicle's multi-function display (MFD), but I suppose exceptions exist.

OK so I have tried over filling the tyres and holding down the button and yelling at it but nothing has worked so far.

First and foremost, let's eliminate the basics before taking the more expensive and time-consuming route of diagnosis and/or replacing parts.

Read the owners manual carefully and ensure you are completely familiar with how the TPMS operates on your particular vehicle, which may be different to vehicles using an indirect TPMS.

There are two sets of tyre inflation pressures for the vehicle: one set for "normal load" (or half load) and another set for "full load". Likewise, IIRC, there are also two threshold settings for the TPMS: "normal load" and "full load". This means that the system will give a false alert if you inflate the tyres with the "normal load" figures while the system is set to "full load".

One must also take temperature into account. For a fixed volume, pressure increases when temperature increases (gas law). So if the tyre is warm, you need to compensate for this by approximately adding between 2 to 4 psi.


For example, if the recommended inflation pressure is 39 psi (with TPMS set to "normal load"), then:

Warm tyre (car driven to service station): fill at 42 psi.
Cold tyre (ambient temperature): cools down to 39 psi = correct inflation pressure.

Warm tyre (car driven to service station): fill at 39 psi.
Cold tyre (ambient temperature): cools down to 36 psi = underinflated, which triggers TPMS warning alert.


It is best practice to adjust the inflation pressure when the tyre is cold (i.e. at ambient temperature).

If none of that fixes the issue, then you may have to look at getting the problem properly diagnosed.

How do you go about replacing the batteries?

With great difficulty, I imagine.

The lithium coin batteries installed in many TPMS sensors are not designed to be user-replaceable. The battery will either be soldered on (tab configuration) and/or encased with a potting compound (usually synthetic resin) to protect the electronics from excessive heat and vibration.

In addition, TPMS sensor manufacturers usually use industrial-type batteries designed for high-temperature resistance, which might make them more expensive to purchase than ordinary batteries.

I don't suppose this issue would be covered by Allianz Extended Warranty? I haven't had to use them for any claims so far...

The usual procedure is to replace the entire sensor, warranty or otherwise.

Maybe try contacting Allianz and ask if the policy covers TPMS sensors.

[buzuki]

The TPMS sensors are a service item. 7 years i believe. Whole sensor is replaced

[Diesel_vert]

Generally speaking, most vehicle manufacturers cover TPMS sensors under the original factory warranty, if there's an accompanying fault code (including low voltage or low battery faults) and there are no obvious signs of damage caused by you or a third-party (e.g. tyre fitters).

For any other warranty, including extended warranties promoted by the vehicle manufacturer and sold through a dealership, it will depend on the policy.

[Guest001]

Saw these on Ebay

VW Audi TPMS Sensors 315MHz Set 4 S018BK 2 3458294761 SE55001 Tire Sensor | eBay

I asked the seller about the batteries and he replied saying the whole unit must be replaced if the battery dies

[RRR036]

Thanks everyone. I just tried filling up with 43psi after driving to the servo (cold fill to 39psi) and it's still complaining.

I suspect that one of them has been damaged after having the tyres changed by the previous owner.

Out of curiosity, what do people usually do when fitting aftermarket wheels? Buy new sensors off of eBay or remove the sensors from the standard wheels?