Tyre pressure sensor issue

Moanin

Good morning,

I recently got new tyres fitted on 2018 Audi a4 and afterwards my tyre pressure sensor warning appeared on the dash. I checked all pressures and they were okay and reset it on MMI.

It has come back on again after a few days driving even though tyre pressures are okay (I checked them again).

Would the tyre fitter have damaged a sensor I wonder?

Any opinions or experience of similar?

Thank you

XsApollo

Are the tyres the right size and load rating, and are they inflated to the correct PSI?

there is no sensor on the Audi, as far as I know, it’s measured through the ESP/ ABS and wheel rotation, so if it was faulty it would likely be throwing up other faults.

they are prone to failing ABS sensors tho, just replaced 2 in my A6, it would be throwing up a lot of other faults when they go.

XsApollo

oh and another thing check the wheel nuts are tight.

Moanin

https://www.boards.ie/discussion/comment/120247254#Comment_120247254

Okay Thank you.

Are you sure that there are no TPS sensors on B9 A4?

Yes they are inflated to correct PSI. I've checked this after waring came up on MMI

Moanin

https://www.boards.ie/discussion/comment/120247304#Comment_120247304

I never checked this.....

XsApollo

https://www.audihelp.com/auda-14-tyre_pressure_monitoring_system.html

doubt there is a sensor, lose wheel would cause issues also, so check they are tight,

it’s probably written on the receipt to check the nuts after 50km or so.

Moanin

https://www.boards.ie/discussion/comment/120247378#Comment_120247378

Yes it is indeed written on receipt and posted in yard where I got tyres .

I will check this and report back.

Thank you

creedp

https://www.boards.ie/discussion/comment/120247400#Comment_120247400

This always amuses me. The place I go actually hands out a slip of paper asking you return within 48 hours to check the nuts. As if people have to bloody time for that carry on. Why can't they tighten them properly in the first place? Ive yet to come across a place that services brakes giving the same warning.

TherapyBoy

https://www.boards.ie/discussion/comment/120247662#Comment_120247662

Something (a wheel nut) is attached to a vital piece of your car (a wheel) & is tightened & loosened by rotating one way or another, which is rotated one way or another while you’re driving. Things can end up too tight or too loose. Too tight can end up stripping threads on the bolt or otherwise jamming the wheel onto the car, not ideal if you get a puncture somewhere. Too loose can leave you starring in a YouTube video when your wheel decides to run for freedom when you’re driving down the road.

They’ll retorque your nuts for free, thank them & be on your way.

creedp

https://www.boards.ie/discussion/comment/120248031#Comment_120248031

I retorque my own and save them the job and me the journey. If they can't do it right the 1st time I don't trust them to do it right at any time. As I said I go to an independent guy to do my brakes and Ive never been asked to come back to retorque my wheel nuts, nor would I consider it necessary. Maybe the brake guy is negligent or maybe he's confident thats its not necessary.

Either way if people are more comfortable to return to have their wheel nuts retorqued then absolutely go ahead.

User1998

https://www.boards.ie/discussion/comment/120247662#Comment_120247662

Its so they are not liable for your wheel falling off

Jim_Hodge

Did you do a pressure sensor reset by holding down the reset button?

TherapyBoy

How does your independent brake guy know the brakes are working after he’s finished working on them?

creedp

https://www.boards.ie/discussion/comment/120248508#Comment_120248508

I've never asked him as I suppose I'm trusting him to know what he's doing.

colm_mcm

I thought they’d be the same as other VW Group stuff and not have actual sensors, they usually use the ABS sensors to detect if one wheel is turning at the wrong speed relative to the others.

Jim_Hodge

How do i reset the Audi A4 low tire pressure? (vehiclehistory.com)

How to reset Audi A4 Tire Pressure Light 2018 - YouTube

Moanin

https://www.boards.ie/discussion/comment/120248500#Comment_120248500

I did on the MMI screen

Moanin

https://www.boards.ie/discussion/comment/120247400#Comment_120247400

Well, I checked all nuts to see if any loose ones and there wasn't

Al tyre pressures ok and I reset MMI even thouigh no warnings coming up on dash...

Moanin

https://www.boards.ie/discussion/comment/120249851#Comment_120249851

Correct

Buffman

https://www.boards.ie/discussion/comment/120247358#Comment_120247358

Some Audis have direct TPMS as standard, some only have indirect and some have direct as optional. AFAIK on a B9 A4 direct TPMS was an optional extra.

It sounds like an option you have and has all the symptoms of a broken sensor post tyre change, although I've also seen a TPMS light after a wheel rotation as some cars can require the different wheel sensor position to be reprogrammed. To be 100% sure what the issue is you'd have to get an OBD scan which should tell you what it is.

The sensors themselves aren't too pricey, it's just the hassle of getting one fitted etc. If it is broken, I'd be asking the tyre place to fix their damage.

TPMS light is an NCT fail on any post-2015 car so it will have to fixed.

https://www.auto-doc.ie/car-parts/tyre-pressure-control-system-10934/audi/a4/a4-8w2-b9/117110-2-0-tdi

creedp

https://www.boards.ie/discussion/comment/120251974#Comment_120251974

I had the same issue after tyres replaced. TPMS seemed to work fine for a day and then warning light came on. As happened so soon after tyres done, went back to fitter who didn't want to know about it. Guy said he checked the sensor before fitting and it was fine. Went to another place and they found the sensor was seperated from valve and rolling around inside tyre. Replaced for €60 as NCT coming up. Since then always mention to tyre fitters before they start work.

Moanin

https://www.boards.ie/discussion/comment/120251974#Comment_120251974

Thank you. car is due a service soon. Mechanic will be plugging it in anyway as part of service so I will see what it throws up.

Moanin

https://www.boards.ie/discussion/comment/120252031#Comment_120252031

Thanks where is sensor located anyway as a matter of interest?

Moanin

https://www.boards.ie/discussion/comment/120252308#Comment_120252308

Another thought.....if sensor is rolling around inside tyre it would damage inside of tyre?

creedp

https://www.boards.ie/discussion/comment/120252308#Comment_120252308

It's connected to the air valve on each wheel.

creedp

https://www.boards.ie/discussion/comment/120253413#Comment_120253413

Wouldn't think so, its very light and predominantly plastic

Buffman

https://www.boards.ie/discussion/comment/120252308#Comment_120252308

It's part of the valve, a box on the end of it. There are some photos of them in the link I posted.

https://www.boards.ie/discussion/comment/120253413#Comment_120253413

Ye, it's not great but I doubt there's any risk of damage, I'd imagine centrifugal force would keep it in the one position at higher speeds. Tyres are pretty robust. It might throw the balance off alright so the wheel will need to be checked for balance when fixed.

Moanin

The valves were replaced. This is the norm when getting tyres with these guys.

As 1 poster said most A4 B9s don't have direct TPMS so they probably thought this was the same.

I think this car does.

Buffman

https://www.boards.ie/discussion/comment/120253778#Comment_120253778

It would take a very 'special' kind of plonker to replace TPMS valves with normal valves, but nothing would surprise me.

The way it normally works is normal valves get replaced every tyre change, TPMS valves are left alone in place as long as they are OK. Replacing TPMS valves would add significantly to the cost of a tyre change.

Moanin

Update - The car does not have have direct TPMS. After resetting the tyre pressure sensor monitor on MMI last week the warning hasn't appeared.

Thanks to all for contributions!

Buffman

Good news, a lot less hassle when it fixes itself! 😂

Just general advice for everyone, if you know your car has direct TPMS sensors in the wheel, say it to the tyre changer so they can be extra careful with it. 👍️