Tyre Pressure Warning Randomly Activating

[HMG1K]

I've a 2021MY A4 Avant S-Line which randomly activates the low tyre pressure warning alert / light on the dash for no apparent reason.

Over the past year I've checked all four tyres when cold and there is no change to the correct pressure they have been set to (having reset the system in the MMI each time) - or at worse one of the tyres may be 0.5 of a BAR down.

I've also a 2020MY A5 Sportback S-Line with no such problem.

I've had the A4 into the main dealer and they have found no problems or solutions to this.

Any ideas?

 

[Booboo]

Could be an intermittent fault with an abs sensor as I believe the circumference reading is taken from this

 

[Frizzley]

I've a 2021MY A4 Avant S-Line which randomly activates the low tyre pressure warning alert / light on the dash for no apparent reason.

Over the past year I've checked all four tyres when cold and there is no change to the correct pressure they have been set to (having reset the system in the MMI each time) - or at worse one of the tyres may be 0.5 of a BAR down.

I've also a 2020MY A5 Sportback S-Line with no such problem.

I've had the A4 into the main dealer and they have found no problems or solutions to this.

Any ideas?

Could be an intermittent fault with an abs sensor as I believe the circumference reading is taken from this

Cars fault log should show which wheel is activating the warning even though the mmi just displays a low pressure warning. If it’s an intermittent abs sensor fault this should give an idea of where to start looking first

 

[NHN]

As above tbh, if it's abs based version, if not then sensors need checking.

 

[HMG1K]

Thanks all, yes I've the basic in both cars - that is the dashboard just flashes up the low pressure warning. The MMI just has a reset all four tyres option. There's no displaying of what each tyre pressure reading on the dash.

 

[ub7rm]

If you have a tool like Carista or OBD11 when you scan the car it will tell you which specific wheel caused the alert even though it doesn't display in the dash.

 

[fitboyawesome]

I've a 2021MY A4 Avant S-Line which randomly activates the low tyre pressure warning alert / light on the dash for no apparent reason.

Over the past year I've checked all four tyres when cold and there is no change to the correct pressure they have been set to (having reset the system in the MMI each time) - or at worse one of the tyres may be 0.5 of a BAR down.

I've also a 2020MY A5 Sportback S-Line with no such problem.

I've had the A4 into the main dealer and they have found no problems or solutions to this read this guide for e350 psi.

Any ideas?

If you've been driving it for that long at 28 psi, the edges of the tread have certainly worn down very unevenly. Your tyres are likely just making good contact with the centre of the tread now that you have them inflated to the proper pressure, which will cause the car to roll much more easily but less firmly. Till they start to smooth out a bit, use caution in the rain.