Tyre pressure (TPMS) light flashing

[MadJam250]

My TPMS warning light has come on this evening in flashing mode. Does this part way through a journey (after a few miles, 7 degrees C) and turns off after about 30 seconds. I own a 2014 CT200h and after 4 years I have not noticed this before, in flashing mode, but it does come on, permanently, occasionally, when the outdoor temperature is getting colder and tirns off either if the temperature rises or if I manually reset the function. 

Any thoughts please?  Thanks

[steve2006]

Is there anything mentioned in the owner’s handbook?

From what I understand a constant light indicates a tyre pressure problem and a flashing one a problem with the TPM system.

The only sure way to diagnose is a fault code scan but the pressure sensors in the tyres being Battery powered are known to fail.

[LenT]

9 hours ago, MadJam250 said:

My TPMS warning light has come on this evening in flashing mode. Does this part way through a journey (after a few miles, 7 degrees C) and turns off after about 30 seconds. I own a 2014 CT200h and after 4 years I have not noticed this before, in flashing mode, but it does come on, permanently, occasionally, when the outdoor temperature is getting colder and tirns off either if the temperature rises or if I manually reset the function. 

Any thoughts please?  Thanks

It could be just a matter of physics.  With every drop of 10C in ambient temperature, the tyre pressure will reduce by up to 2 bar.

So that could be enough to trigger the system.  It has certainly happened to me in the past.  Using the reset button apparently just resets the system to accept the pressures in the tyres at that moment.

Best answer is to reset all the tyre pressures to the correct level when cold.

Steve’s point about the Battery life is also very relevant.  If you have the original valves then they are eight years old and - depending on mileage - may well becoming to the end of their life!

[MadJam250]

The manual doesn't equate ti my scenario exactly. The flashing light is supposed to indicate an issue with the monitoring system (likely the batteries) but after it flashes it goes out. Makes sense though. Thanks. 

Can the batteries be replaced anywhere or does it have to be at a main dealer? 

[Spock66]

1 hour ago, MadJam250 said:

Can the batteries be replaced anywhere or does it have to be at a main dealer? 

New TPMS sensors will be required as the batteries are not replaceable.

[NemesisUK]

3 hours ago, Spock66 said:

New TPMS sensors will be required as the batteries are not replaceable.

Not officially maybe but ...

 

 

[Sherra]

I have replaced all the batteries in all four of mine for £15 pounds, which is considerably cheaper than a quoted £93 each sensor from LPD using Johns brilliant post as the basis.