Guys need your help here.

The lights on my TPM (Tire Pressure Monitor) came on once about 2 months ago, after inspection and making sure non of the tires were flat, I followed the instructions on owner's manual and reset the TPM and had no problem since.

Today he TPM lights came on again, I quickly inspect the tires and they seem to be normal. I reset it again and a minute later after driving, TPM is back. Reset again and it came back again.

So I check the PSI on my tires and all 4 (205/45/17 Continental) appears to have 27PSI. I check with the sticker on the side of the car and it indicates the Normal PSI on my Mini Cooper S is 38PSI, this seems kinda high, I just set my tire pressure to 35PSI. I drove around the block and no TPM yet.

My questions are:

1. What’s everyone tire PSI ?
2. I have 205/45/17 Continental, does this mean I have a run-flat tires?
3. Does your TPM lights came on frequently even your tires are fine?
4. What triggers my TPM?

Thanks!

 

1. Mine is 16" CONTI. According to the manual, 33 PSI for normal driving/36 PSI(+100mph, Full Load). 17" starts from 36/38 PSI to 41PSI Full Load +100mph.
2. S comes with run-flat regardless of size (16"/17", SUMMER/All Season).
3. My TPM came out only once in a very cold winter morning (29 PSI all 4 tires, initial at 33-34PSI). I do check my tire pressure once a week.
4. PSI drops too much compare to initial PSI reference (All four tires, or one of them).

 

I run my tires at 34 PSI it gives me a decent ride for daily driving.
If i'm running aggressive then I bump them up to 36- 38 for better stability (less sidewall roll).
the TPI is basically just a pressure activated switch connected to your tire valve. it is activated (turns on dash light) when the pressure drops to a pre determined amount. the reason why they are in cars is because most people dont check there tire pressure enough. If ever. and having these monitors helps in maintaining optimal ride, and fuel economy.

 

Thank you guys for your wisdom. I am going to drive it around a little bit (prob take it to the beach) and will report with the TPM, hopefully it will stay quiet now

 

I run 36 to 38 in the front tires, and 34 to 36 in the rear on 205/45-17 tires (no passengers).

 

I have the basic 15 inch Continental all-weather tires (not runflats) on a 2008 MC. The recommended pressure is 33 lbs for each tire, but I run 34-35 lbs each - better ride, I think, and it keeps the TPM from coming on too often. I have had mine come on one time and the pressure in one tire had dropped to 32 lbs. So, I just check every couple of months, and keep the tires at 34-35 lbs. These tires are really holding pressure. In many cases, I can go 3-4 months without having to add air.

 

1. What’s everyone tire PSI ?
38 PSI, I also have the Conti all-Season RFs
2. I have 205/45/17 Continental, does this mean I have a run-flat tires?
If you have an S, you have RFs
3. Does your TPM lights came on frequently even your tires are fine?
They used to, turns out it was a TPM sensor gone bad, replaced under warranty. No issues since.

 

Mine came on last week and the lowest tire was @ 28psi. I have been running 35 in all tires.

It was cool and raining that day. I tried to use the 12V pump I purchased to take with me and couldn't get it to work in either the front or rear power points. I got soaked trying and stopped at a station, set them all back to 35psi and reset the TPM and haven't heard from it since.

I later found that my 12v power sockets only work with the motor running.

The pump was fine.

DaveJ

 

Engine does not have to run but the key has to be in the ignition and you should push the start button w/o depressing the clutch. All electrical is on w/o the engine started. This helps you save a couple of dimes on gas.

 

Key in, buton down without starting may be the only thing I didn't try.


Thanks

DaveJ

 

On my 2007 MCS, the cig lighter sockets don't get power with just the ignition on. The engine has to be running. I power a Bass600 subwoofer from the rear socket and it cuts out when the engine is off, but radio still running. The front socket is on the same circuit as the rear.

Probably better to have the engine running while using a 12v compressor. Wouldn't be very helpful to have the right pressure in your tires, but not enough battery charge left to start the engine.

 

Very True! The tires are run flat but nowhere on the battery does it say start flat.

 

Happened to me for the first time last week...back passenger tire also. I added a few lbs and reset the TPM.

I noticed that all my tires were at 35-37lbs...so the manual and door panel says 32 psi...so I let air down to 32 all 4 tires tonight and will rest tomorrow morning before my drive and recheck.

Any advice on setting at vs above the stated amounts in the manual? What can I expect from tight tires vs low times? I can imagine that gas mileage may be better at higher pressures?? But profile will be plumper...making it wear more in centerline?

 

It's odd that you guys have to reset the TPMS.


I had the light go on twice now, and it reset itself each time I adjusted the air pressure back to norm.

 

The two biggest things to notice from higher pressures would be:
- More ride harshness (due to stiffer sidewalls from more pressure)
- Lower rolling resistance for slightly better MPG (due to less tire deformation when rolling)

It is possible that you could notice more responsiveness to the wheel, and slightly better road-holding in corners.

You are not as likely to notice slightly longer stopping distances and slightly easier wheel-spin on acceleration, but they are likely there.

Fairly few modern tires actually exhibit noticeable extra wear in the middle of the tread from higher pressures. Some do, but most do not. Older tires (e.g., one or two decades ago) definitely did.

Some run-flat tires actually exhibit less harshness at slightly higher pressures for some reason.

Many tires get noisier at higher pressures, but not all do. Often the difference isn't really noticeable.

You are usually "safe" going up to the maximum printed on the sidewall, but the trade-offs are not worth it for most people.

 

On my first mini, an '08S with 17' wheels and sports suspension, I experimented with tire pressures and also found that lowering the pressure from the recommended 38lbs., that the ride became harsher.??????????
On my '12S, I got the stock suspension with 16" runflats and again, the ride seems to be the best at the recommended pressure( 33lbs.).
On my '08, I replaced the runflats at 11,000 miles( I just could not stand the tramlining). The replacement non runflats reacted typically to changes in pressure ( lower softer, higher harsher but a little better steering response).
On my '12 I have 16,000 miles and plan running them until they're worn out. After that, I am thinking a 17" Conti DW or DWS.

 

Thanks buddy!! this is very helpful. At 32psi...I didn't notice driving difference in my 1.5 hour commute... My MINI is my only joy during that long drive...

To answer why we need to reset the TPM...maybe the 2013 Countryman PC interface with Nav system is different from '11& '12s...