TPMS Slow to display.

[Redsteve]

Good afternoon to you all.

I hope you are all ready (or nearly ready) for Christmas.

A couple of weeks ago I had two new tyres fitted to the front of my 2007 LS460.

Before I had the tyres fitted the TPMS system would display the tyre pressures within a few minutes of stating the car, most of the time it was just a few seconds.

About three or four days after having the new tyres I noticed one of the sensors was taking a long time to display the pressure. It has taken up to 15 minutes to register the pressure. 

Once the pressure has been registered it seems to react at the same rate as the other sensors i.e. pressure increasing as the tyres warm up and decreasing as they cool.

If I turn off the car and leave it for a few minutes and then restart it then the offending sensor reacts within a few seconds, just like all the others.

The sensor seems to register slower the colder the outside temperature is.

My question is

Do you think it is just the Battery in the sensor going flat or do you think it might have been damaged while the new tyres were being fitted?

Regards.

Steve.

[BigBoomer]

Almost certainly the Battery in the sensor.
One of my motorcycles has TPMS and after a few years they get really slow to react, at first only in the winter, then all the time, and soon after that the sensor Battery low warning comes up. 

[scythe]

I agree with BigBoomer - almost certainly the Battery.

The irritation is that after the car registers its failure after several tries, it gives up completely on the tpms altogether, and shows a permanent error instead. 

On one side of things, it won't fail an MOT. There is no legal compunction to have a working tpms system on a 2007 car - I know, cos I had this with my 2007 LS, and it passed its MOT twice like this.

The other side is, its just an irritation and having dirty fingers having to unscrew the caps on the tyres!

It will cost you about £45 per valve, and maybe when you get your next tyre change you should just plan to do the lot, if you're keeping the car.  Don't forget the spare, either!

: o )

 

[Redsteve]

Thanks for your replies guys.

I was leaning more towards the low Battery theory myself but it is nice to hear it from someone else too.

I am a bit annoyed it has happened after having the new tyres fitted as now I will have to pay someone to remove the tyre so I can get to the valve when it has only been on a couple of weeks.

I am considering just fitting the spare and, after accessing the dodgy sensor, just trying to replace the Battery within it.

I have seen a video on YouTube and it looks fairly straight forward.

My thinking is that if it all goes horribly wrong then I will just have to buy a new sensor anyway.

I have a bit of time off work in February, so if I can wait until then the car can be parked up for a few days for me to take my time with the job.

Thanks for your advice.

Merry Christmas to you all.

Steve.

[Malc1]

I was reading that the MOT year for working TPMS is 2012 and the earlier ones are just nice to have and don't have to function

Malc

[Spock66]

2 hours ago, Malc1 said:

I was reading that the MOT year for working TPMS is 2012 and the earlier ones are just nice to have and don't have to function

That's correct, but I do find it a useful feature, if you shop around the sensors are not hugely expensive.

[Redsteve]

Good morning Guys.

I thought I would just give a quick update on this thread.

My scheduled time off from work got cancelled and the sensor was failing to register at all on the system so I just went to my local tyre and exhaust place and asked if they could fix it for me.

They checked all the batteries in all the tyres with some bit of witchcraft and established that four of the five batteries were still "In the green" but the one which stopped working "Wasn't even showing up in the red".

They replaced the offending sensor and now the car is back to normal. The total cost was £80 which, although is a chunk of change, is not too bad.

Happy days.

Take care.

Steve.

[LenT]

1 hour ago, Redsteve said:

The total cost was £80 which, although is a chunk of change, is not too bad.

Suppliers seem to suggest a Battery life of between 5 - 12 years, depending on use. So if these are the original fittings, then you’ve done pretty well.

[BigBoomer]

The TPMS Battery life is mostly mileage related rather than age related.
When the wheels are not turning the sensor is off and not using the Battery.
Since the sensors have long-life lithium batteries their lifespan is over 10 years if not used.

[Redsteve]

Hello Guys.

My car has done 80000 miles so maybe it was the original sensor.

It's a bit strange that 4 wheels still have good batteries and 1 was bad. Maybe the previous owner replaced the sensors on the 4 wheels on the car but never changed the one in the spare.

Take care.

Steve.

[scythe]

Yeah... lots of places seem to sell replacement sets - but there are only four sensors in the set. 

The car should be good, then, for the next 16 years

: o )