rb23lb

Have any of you seen the blood red (in color) screen of death that tells you to check your tire pressure?

It starts out with the normal monochrome screen.... then randomly I will get this crazy bright red screen and a beeping alarm noise telling me to check my tire pressure...

I pull over, check the pressure with my portable gauge, everything is normal psi on all the tires...

I turn the car back on, boom, message is gone...

about 5 minutes later, crazy red screen comes on again...

just went to lunch, now it wasnt on this time

i assume i have a faulty pressure sensor that is tripping false alarms...

if i remember correctly, I think someone else mentioned one of their sensors came loose and they heard it clinking around?

mine all seem to be secure... pretty weird though...

although I must say, I am impressed with the bright red color of the instrument panel... i had no idea that it was capable of such vivid color, when it normally rests in monochrome

MBTex

Yes that happened to me as well. Turned out the TPMS system just needed to be reset due to the cold weather.

If you reset the TPMS it should be ok, just make sure to check the tire pressure first since it will reset to the current pressure.

MBTex

One other thing...your post didn't mention whether or not you checked the spare tire. If you didn't check that one as well you should. That could be the culprit.

Bokx_350

Same here. A quick reset should fix the problem, setting the current value to the standard one.

rb23lb

the spare has a sensor that is linked??? what wireless protocol does it use to transfer the information to the cars computer???

Savage c-300

wow thats crazy, ill keep this info in mind if it ever happens to me

misterng

RLE

<<One other thing...your post didn't mention whether or not you checked the spare tire. If you didn't check that one as well you should. That could be the culprit.>>

The mini-spare has no sensor, just an ordinary valve stem. So, if you have a flat, the system will see only three sensors and eventually go off line except the little orange warning symbol in the speedo will flash for a while and then go steady and you will get a message Tire Pressure System Disabled (something like that) about every ten minutes which you will have dismiss with the OK button.

I know this because my TP system has never worked since one sensor was removed after it was sheared off by the tire mounting machine when tires were mounted on my 18s. It's finally being replaced today and the system is back online with my winter tire wheels on the car.

MBTex

No clue how it works...just reposting information from other posts.

MBTex

Good to know...will keep me from shouting expletives at the car while trying to check the pressure of the spare.

ryanrohaley

It's not quite a wireless protocol like IEEE 802 that PC's use. The transmitters are in the tires and there is a receiver (in the dash I believe) that has an antenna and a built in radio component that just uses radio waves.

crow944

First time I saw that bright red display is when i was backing out of a parking space and a accidently must of press down on the break lever just under the trunk release. The red displayed on and the engine cut out.

stealtheo

Same exact problem on my 08 C350 - Dealer replaced entire control unit. Will show a code that you can only dealer can read. Tech explained that the code was only showing on a second layer (sub menu in DAS) and that with a OBDII reader would of went undetected.

RLE

<<The transmitters are in the tires and there is a receiver (in the dash I believe) that has an antenna and a built in radio component that just uses radio waves.>>

The receiver unit is in the trunk on the left side.

mac911

So what happens if you get replacement tires? If you get replacement tires somewhere other than the dealer, do you lose your monitoring?

peabers

Sensors are attached to your wheels, not tyres. You'll either have to move your OE sensors to the new rims, or get a second set of sensors for the new rims. ~$300 from TireRack. I believe RLE got a set from them.

(and yes, I have learned that in Canada we don't get the sensors... uses ESP to monitor rotation differences amongst the tires to determine if there is a potential loss of pressure. )

To the poster who was fascinated by the red display... with Keyless Go, if you start the car and then walk away with the key/transponder, the display will go red and indicate "Key Not Detected". I have yet to experiment if I can continue to drive way without the key.

RLE

<<Sensors are attached to your wheels, not tyres. You'll either have to move your OE sensors to the new rims, or get a second set of sensors for the new rims. ~$300 from TireRack. I believe RLE got a set from them.>>

Tire Rack quoted me $70 each so I bought a set from Caliber Motors in Anaheim for $59.04 each plus shipping.

The same Schrader units for forty bucks less per set. You will also have to order the nuts (000-401-07-14) which are extra. I paid $2.59 each at my local dealer.

Caliber's number is 1-800-252-6877

themundy

Same thing happened to me....cold weather strikes again.

Dreamasasn

The tire pressure issue is a manufacturing/computer problem--I'm having the same issue. It seems there may be a recall on this as they are a couple of other owners of the 2008 c300 that are having the same problem.

It seems Benz always goes through this process with their new models. There was a similar issue with the E Class a few years ago.

The temporary solution:
Reset the system

As a side note it's my understanding the dealer I bought my car from had to buy back two cars and send it to Germany to figure out what the probelm is..stay tuned for more info.
~KA

jstaneff

When my tire picked up a screw and it developed a rather quick "slow leak", the warning I had was the red screen. Cool.

Once the tire was fixed, the TPMS wouldn't turn off the tire warning idiot light. I had to reset the system for that. Once reset, it's been fine.

As with much else on this car, I find myself wanting to do a code review on their electronics. I suspect that the design criteria for the software was developed in a vacuum without much real-world input. Oh well. It could have been Microsoft ... reboot!