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DV52
06-02-2014, 09:12 AM
I'm interesting in hearing other Golf owners experience with the mk7's tyre monitoring system. The manual talks about the Golf's ability to detect vibrations caused by flat or deflated tyres. I reckon that a no-one needs a tyre monitoring system to tell if there is a flat tyre, but the low pressure detector sounds interesting! I've not had either of these events occur on my car (as yet), but I'm intrigued by the concept of a transducer in the car (somewhere) being so sensitive that it can distinguish normal car vibrations from those related to deflated tryes.

Does the tyre monitoring system actually work and what are the conditions that need to occur before the little yellow tyre symbol pops-up on the MFD? How low a pressure does the tyre need to be? I assume that vehicle speed is an important determinant of the sensitivity of the detector.

Has anyone had actual experience with the tyre monitoring system and if so, what happened?

andrew7
06-02-2014, 10:11 AM
Cant speak to the MK7 but my MK6 GTI tyre pressure light went on last year, doesn't identify which tyre, requires a check of all pressures (I think my RHS driver tyre was a little low) and once your are satisfied post reinflation hit the reset button located inside the glove box. No problems since. Not sure what the default standard pressure is but i attempted to ensure all tyres had the same pressure before resetting the sensor.

brad
06-02-2014, 10:59 AM
In the Golfs it's done off the ABS sensors looking for a difference in rotational speeds.

The more expensive passats use a sensor inside the tyre with a radio link thingy back to the ecu or BCM.

I know lots of people that wouldn't have a clue one of their tyres were flat - esp the rear on a FWD. If you are running a really low profile or an RFT you can't even tell from a visual because the sidewall doesn't deform.

Nauend
06-02-2014, 11:09 AM
I've experienced the tyre pressure warning. One of the tyres had been punctured by a nail, so was a slow leak. When I received the warning, I could not see any difference in pressure of the tyres by looking at the tyres. Happened to be on my way to get the gearbox oil recall done, and VW confirmed the puncture. I ended up driving with it that way for a few trips while bob jane sourced a replacement.

Tom87
06-02-2014, 11:18 AM
In the Golfs it's done off the ABS sensors looking for a difference in rotational speeds.

The more expensive passats use a sensor inside the tyre with a radio link thingy back to the ecu or BCM.

I know lots of people that wouldn't have a clue one of their tyres were flat - esp the rear on a FWD. If you are running a really low profile or an RFT you can't even tell from a visual because the sidewall doesn't deform.

which is pathetic, because plenty of "lesser" models now have proper pressure sensors in each tyre. I'm thinking of the majority of the Hyundai range and even ChryslerFiat group models since my2013...

It was alright in 2009 for the Mk5 and 6 to be like this but certainly not the Mk7.

Anyway. Random rant...sorry :)

Diesel_vert
06-02-2014, 01:44 PM
An indirect tyre pressure monitoring system (TPMS) is based on the principle that an underinflated tyre has a smaller rolling circumference and thus rotates more quickly, as well as a different frequency and amplitude, to that of a correctly inflated (reference) tyre. The vehicle's onboard computer is setup and programmed to detect this difference via the wheel speed sensors, and alert the driver as necessary.

This system doesn't measure a tyre's inflation pressure, so it works with values relative to whatever the system has been set at. Thus, the system is dependent on the user to ensure the tyres are inflated at the correct pressure if the TPMS is to function as intended.

Unlike first generation systems, a second generation indirect TPMS is able to identify which individual tyre is punctured or underinflated.



Contrast this with a direct TPMS, which uses inflation pressure sensors attached to the air valve and installed inside each wheel on the rim flange (the spare wheel may or may not be included). These sensors communicate with the vehicle's onboard computer wirelessly and measures inflation pressure as well as temperature, so this system works with absolute values, eliminating the need for user calibration (read: miscalibration).

However, inflation pressure sensors (which aren't always inexpensive) need replacing every 8-10 years, because as a consequence of trying to protect the electronics and casing from excessive wheel vibration, the lithium batteries used to power them are not normally user replaceable.



For any TPMS according to EU regulations:
Upon adjusting or calibrating the inflation pressure, the system is to be given 20 minutes of learning time.
The puncture threshold is 20% below operating (warm) pressure, detected within 10 minutes.
The diffusion threshold is 20% below operating (warm) pressure, minus a further 7 kPa (1 psi), detected within 1 hour.
The system must be able to operate from a speed of 40 km/h.

For any TPMS according to US regulations:
The threshold is 25% below the recommended (cold) pressure, detected within 20 minutes.

To the best of my knowledge, there is nothing in the regulations for an upper threshold to be established.

pologti18t
06-02-2014, 02:54 PM
which is pathetic, because plenty of "lesser" models now have proper pressure sensors in each tyre. I'm thinking of the majority of the Hyundai range and even ChryslerFiat group models since my2013...


You'd be wrong then. Name a hyundai model in Australia with pressure sensors in the wheel?

Tom87
06-02-2014, 03:26 PM
You'd be wrong then. Name a hyundai model in Australia with pressure sensors in the wheel?

99.9% sure it was a new i30 I was in last year which had the individual tyre pressure read out in the MFD.

b c
07-02-2014, 12:09 PM
Had a low pressure warning on the left front tyre earlier this week - Mk7 Highline - so it does identify which tyre is suspect. However, when I checked the tyre the pressure seemed to be OK. Checked all the pressures that night and there were some differences between the tyres, now evened out and all good.

kennyc
07-02-2014, 01:13 PM
I can confirm that it does work on the mk6 GTI.
Mine was going off every few days and had to keep pumping the tyres. Mainly the RHS passenger Tyre.
Took it to the Tyre shop and there was a screw in the Tyre. So it does work!.

cox11
07-02-2014, 01:44 PM
I have it in my Mini Cooper s. It generally works well, but the other day it went off so I went down to the servo. Turns out all the tires were ok. I guess sometime you will get a false alarm

brad
07-02-2014, 04:03 PM
Had a low pressure warning on the left front tyre earlier this week - Mk7 Highline - so it does identify which tyre is suspect. However, when I checked the tyre the pressure seemed to be OK. Checked all the pressures that night and there were some differences between the tyres, now evened out and all good.
Wouldn't you inflate to required pressure then press a button to let the system know what the latest point of reference is?

b c
07-02-2014, 04:05 PM
Wouldn't you inflate to required pressure then press a button to let the system know what the latest point of reference is?
I thought the pressure was OK when I measured it. Checked the right front and there was a difference, so evened them up after satisfying myself that I didn't have a "flat". Checked all four that night. Don't know why the light came on, or why it through the front left was "low", but it was different. Reset the system when tyres were adjusted and haven't seen the warning since.

DV52
07-02-2014, 10:33 PM
Had a low pressure warning on the left front tyre earlier this week - Mk7 Highline - so it does identify which tyre is suspect. However, when I checked the tyre the pressure seemed to be OK. Checked all the pressures that night and there were some differences between the tyres, now evened out and all good.

b.c.: How did your Mk7 tell you which tyre was faulty? I thought that the only indicator on a mk7 was the yellow tyre symbol on the MFD.

b c
12-02-2014, 08:41 AM
b.c.: How did your Mk7 tell you which tyre was faulty? I thought that the only indicator on a mk7 was the yellow tyre symbol on the MFD.

Checked the "Car" menu and it listed the outstanding issues (was also low on fuel at the time). It said which tyre it thought was low. Suspect it was a false positive though.