TPM tyre monitor

[resovoir]

I am referring to yr 20 GS 1250 with cast wheels.

I had new tyres fitted and all ok for four separate 100 mile journeys. Fifth journey at start of journey tyres pressures indicated as all ok. Then as journey goes on tpm indicated lower and lower pressures the the STOP and check instruction and the flashing red triangle for the rest of the journey. When got home checked pressures and all ok.

I am reluctant to blames tyre fitter as all was ok for the first four journeys. I believe these devices have a battery that may be the cause, but obviously reluctant to take tyre off at this stage. As the vaves goes into on of the legs of the cast wheel how des it link to te sensor. Does anyone have a diagram please
Many thanks

 

[philbuck]

Can't help with the 2020 GS, but I suspect it's almost exactly the same as previous ones.

A rectangular TPMS unit bolts into the wheel well and allows the air straight through it (ie on inflation).
This sealed unit has a hole which then sees the air pressure within the tyre and wheel, The onboard battery (when activated), reads the pressure.
Don't know why it's dropping !
This sensor feeds the data to the RDS unit which in turn feeds it to the instrument cluster for viewing.

 

[philbuck]

 

[resovoir]

Cheers Phil

 

[ChazzyB]

View attachment 526594

To add, the fixing bolt is hollow and screws into the 'spoke' which carries the inflation valve.

Batteries in sensors shouldn't have expired after two years from new. I've had two BMW bikes with TPMS at over three years old and no probs with the sensors. OTOH, a chum was unlucky enough to taken in by a snake-oil salesman's pitch about a tyre sealant liquid not affecting TPMS sensors. It did...