"Service TPMS" warning with valves from eBay

I have just fitted a second set of wheels for short term off road use. Rather than buying sensors for the wheels I bought a box to spoof four sensors from Iron Gates (search SpoofTPMS).

This mimics the sensor output and keeps the TPMS system happy, even if I ‘air down’ off road and was considerable cheaper than four sensors.

In the UK if TPMS is fitted it has to be working and it’s a MOT fail if it’s displaying an error message, although I intend to swap back to my standard wheels after a few days.

The term you are looking for is:- "Sods law".

Roger

mlines wrote:

On the Jimmy the sensors report angular velocity. As each wheel turns at a different speed when turning corners, the tpms computer can calculate which corner the wheels are on by the difference in rotational speed. The receiver has to also be mounted off the centre line of the car as it has its own sensor to measure it's angular velocity. This internal sensor means it knows the vehicle is turning and which direction is turning and as it knows the current angular velocity of the wheels as well then it knows which corner the wheels are on.  If one wheel is not reporting then it has one set of information missing so it doesn't then know where any of the wheels are.

I am humble enough to tremble before questioning the master, but are you sure you aren't mixing the TPMS with the ABS?  

Sad to report that my limited OBD2 tool didn't detect any trouble code while the error was on. I think I will make a visit to the tire shop at some point to swap my original valves. The error is not the end of the world, but when it's on, the whole central dashboard becomes unusable.

That's so strange, since the valves actually work and report very accurate pressures every time I check the service menu. There is also a correct Low tyre pressure alarm when I air-down to 10-12 psi for off road. It's only when the car becomes stationary for a few minutes that the error appears every time.

Jacket wrote:

It's only when the car becomes stationary for a few minutes that the error appears every time.

My guess would be that the sensors go in to a sleep mode when stationary after a few minutes to save power.  The Jimny TPMS then displays the error as it doesn’t get any data from the sensors and possibly has to then re-learn, possibly requiring the engine to be off for 20 minutes or more.

From Suzuki, with my emphasis added

Tire Pressure Sensor
Tire pressure sensor consists of a pressure sensor, acceleration sensor, temperature sensor, control section, transmitter / receiver, battery and air valve.
Each tire pressure sensor assigns an individual ID code. Tire pressure detected by the tire pressure sensor, along with the ID code, rolling angle position, temperature, battery status, is transmitted to TPMS control module on the radio wave.
In the condition that 15 minutes have elapsed since the last driving of vehicle, when you start driving and the tire revolves at approximately 25 km/h (16 mile/h) or more, the pressure sensor transmits data to TPMS control module at 16-second interval (fast mode).
And, when the driving is continued for 640 seconds, the pressure sensor transmits data at 64-second interval (active mode).
However, when the acceleration sensor does not detect wheel rotation with the vehicle speed lower than approximately 25 km/h (16 mile/h), the data is sent to TPMS control module at 19-minute interval to prevent battery power consumption (save mode).
TPMS Control Module and Low Tire Pressure Warning Light
TPMS control module receives signals from 4 tire pressure sensors, identifies data by the ID code of each tire pressure sensor and uses the identified data to compare air pressure in each tire with the tire pressure value that was configured in TPMS Setting Procedure. When tire pressure is judged to be lower than the specified value, TPMS control module turns on low tire pressure warning light in the combination meter and stores DTC in its memory. Also, when a fault in the system is detected, TPMS control module blinks low tire pressure warning light for 75 seconds and then the warning light remains lit, and stores the DTC in its memory.
TPMS control module has positioning function of tire pressure sensors as well.