2007 W221 TPMS High Line sensors

[Botus]

my car has individual BT tyre pressure sensors....

I know the codes, and I programmed a set of autel ones as the right ones for the car, with the right codes.....

they are now on the car, but not giving me a reading.... I'm also confused how the car knows how to cope if you move the wheels round.... my bike can't. it has to have each wheel coded to each location ….. and because I didn't fit the tyres and they are directional, I had to put them on different locations on the car


do you think its this ? the tyre guy said it will sort itself out..... if that's the case how many on off cycles would it take....

 

[Botus]

strange car.... still not working inside the car

no faults or messages displayed to the driver (other than "tyre pressures will be displayed after a few minutes driving" - if you go through cluster menus system to find this section)

put diagnostics on it,
no faults....
go in to TPMS section,
all 4 sensors display with an individual BT code (exactly as the car had - which is how I edited them)
each wheel sensors is there and working,
all four giving both temp and pressure read outs (in diagnostic tool)
each sensor shows as having "automatic start up" (whatever that means)

decided to reset ref pressures.... and rather than the usual accepted or what ever message you get …. I get "TPMS system restarted" message and then it's back to its tea break - (other than tyre pressures will be displayed after a few minutes driving )

deeper dive into TMPS saved records shows what I think is actually live data and working here... but with how many km it thinks each sensor has travelled

I just did the last bit with a snap on scanner (which gives me miles).... its suggest it was 7C when this was last done.... (together with the mileage), so I now I think means it grabs a copy of info (like the mileage, pressure and temp info) "saved" when the reference pressures where last "reset"

 

[Botus]

last night I discovered there may be "an element of operator error" in the mix…

looking at results of the original TPM Sensor locations and what Snap on and Autel say are on the car now.... they all match ! (which I know was very unlikely due to the way the tyre fitter put the tyres on the wheels),

so I fired up the autel sensor programming kit to check the programming of each sensor, the two rears were OK, but somehow the same code as LR was on the FR... Which I find particularly strange. In diagnostics it was showing each corner having a temp and pressure reading.... but I now know "one wasn't a valid code to talk to the car" (so I should have had 3 readings, unless because it was a duplicate it could see 4 but as only three match what it expected it wasn't happy)

which is just like a BMW bike for a silly reason "overall safety", rather than show which are working happily alongside the troublesome ones, it shows nothing, but the bike throughs a warning the system is not happy and the merc didn't

will have to see if 4 codes matching the original in the original locations helps.... I can image seeing 2 of the same at each end of the car will have been interesting....

 

[Botus]

so its seems very much like the bike.... they deliberately try to hinder diagnosis and make it slightly less safe than it could be.... if one plays up, they all play dead (very clever !!!)

now... having written each autel sensor at the original locations of the merc sensors, it all works within a hundred yards of driving

nice to see a tyre fitter who can't get within 3 PSI on each wheel

 

[Botus]

nice.... they now do one sensor that does either frequency (autel's 433hz ones are orange for the Mercs - but some use another frequency)

all you need to do is get them fitted on the wheels, then use diagnosis to grab what the car thinks its got in each corner and copy this code to the wheels at home with any laptop

https://www.ebay.co.uk/itm/SALE-Aut...331728?hash=item1f104aec10:g:xuAAAOSwIf9ex6lK