Hi all, 

just after some advice. Recently purchased 2015 Ford Focus Zetec 1.6 diesel. After around 15-20 miles of driving a warning presents on the dash to say tire sensors not detected. This problem presented last week with no recent tire change or damage. I initially took it back to garage purchased who just reset the tpms light and stated tire pressure were fine. The problem has subsequently occurred several times and today I took it to a local tire and exhaust garage.  They completed a diagnostic with no faults registering presumably as I had reset the TPMS through driver assist. However he noted front DS tire was at 24psi should be 31. He inspected the tire for puncture however couldn’t find anything, I returned to the garage shortly after as the light had come on again with the same message. This time he inspected the tyre valve, stated there was a slight leak and corrosion but nothing to warrant triggering the TPMS. Spoke to ford who said sounded like the valve, so at a loss. Any suggestions or previous experience within this would be greatly appreciated. 
 

Regards,  

 

Joe

I've mentioned this before, but I would venture a trip to your local KwikFit. They have TPMS diagnostic equipment and if you do need a new valve/TPMS sensor, can supply & program much cheaper than Ford will want!

Oh, just checked Ebay, genuine Ford sensors are as cheap as chips, who'd have thought! (around £7...)

I second Stephen here; can you be sure that car hasn't had a tyre and valve change and the valves put back to non TPMS ones? Did the garage fit new tyres, or were there any tyre related advisories on the last MOT? I would be inclined to suspect either a bad fitting broke one or one/multiple have been replaced with normal valves on last tyre swap. Do you have fairly new tyres on either/both axles?

I'd buy diagnostics cable and put a copy of forscan on a laptop....  then see what it says.

there are two types of how to know its got air in a tyre.... sometime starting around 2012 more and more legislation came in for Europe making it mandatory to tell the driver about the air in your tyres

1) the cheap nasty idea VAG love, is to look at ABS wheel speed sensors and work out if one is going round faster because there's less air in there

2) a sensor inside each wheel transmits info via Bluetooth on tyre pressure and temperature to the car.  you can have a display that's as useless as the one above (this often confuses owners into thinking they have the cheap ABS type), or (with posher instrument cluster display on higher spec models) see readings on each individual wheel.

we see lots on here where Ford owners seem to have the better sensor derived version, but with the nasty dash display.  Then have issues, I can imaging there'll be some later software updates for the car that could well help, but no one knows about it and even fewer garages would care to install and update.

then of course, because the ford ones look just like a 2p valve stem on the outside many are smashed up when the tyres are taken off the rim, and they never fix or tell you they did it

individual sensors have their own battery that tends to last 70k miles or 9 years, but they could make it do what ever they want.... and these batteries aren't meant to be replaceable

check the tyre pressures, then check the manual for the tyre sensor type fitted to your car and reset the reference... (often hard as manuals seem to muddle info, especially around ABS type and its reset procedure, and the nasty dash display, but proper sensor system)

with type 1) there's a reset to say with this tyre wear and "correct pressures" driving on a smooth road in a straight line, I want this tyre circumference to be the new normal, and within 1/2 a mile the car should get over itself.

with type 2) you can have a limit warning you can reset.  Often for winter tyre use, you can tell the car what you want as the reference pressure and its new reference is taken the instant you press the button

the idea being they throw an error if its a long way from what the car / you set as normal.....