mecca281

Hey guys,

I'm hoping someone can help me figure out my vehicle's tire pressure system (if any)

After parking during lunch today I saw my rear passenger tire was completely flat.
I had noticed a little hesitation while driving earlier but nothing major as I have run flats.

My question is how come it didn't recieve a tire pressure warning?? I have also done some googling on runflat indication resets and it doesn't appear that I even have the option.

Thanks in advance!

beejAMG

im not sure if that comes as standard but I think tyre pressure warning is an option and you might not have it.

mecca281

That seems pretty crappy... Even our 2005 toyota solara even has tire pressure monitoring.

Yidney

Easy way to tell. Are your valve stems black rubber? If so, you don't have it.

Rudeney

Actually, the TPMS on the W209 didn't use electronic sensors. Instead, it used the ESP system to check differences in wheel rotational speed. I believe it can actually be retroactively enabled via SDS, but it really seems worthless since you'd have to really have an almost completely flat tire before it would register. Personally, I hate these nanny systems. Every car we've had with TPMS will whine about air pressure when temps change drastically. And it costs extra to replace tires because the TPMS sensors have to be removed and seals replaced. These systems were just a typical government knee-jerk reaction to the Ford Explorer rollovers. If people would just do weekly safety checks on their cars, including checking tires, we could save billions on these unnecessary devices. (OK, sorry for the soapbox )

lkfoster

While I prefer an active system, the passive system that can be enabled via a STAR machine does work. The system on my '06 C55 triggers at around a 6-8 psig drop. It saved my backside when I got a nail in a rear tire up at Yosemite and had to limp back to Phoenix before I could find a replacement. There's no way that I could have felt the drop without it.

It's actually better than the passive system on the wife's '13 Audi which took around 10 psig to trigger.

mecca281

(Stubs toe) OUCH..Hey, who left this soap box here?

Lol, no worries I appreciate the help. If I am reading your response correctly, a completely flat tire with no warning would most likely indicate an ESP problem? I have had ESP problems in the past and took it to an Indy. I'm not sure what was fixed or replaced all I know is the warning and symptoms went away. Maybe he deactivated something? Actually I do remember him replacing a steering sensor.

Glyn M Ruck

The passive & active systems can be activated or deactivated in the menu on most cars. See your owner's manual.

lkfoster

Apparently it's standard on the '06 Canadian w203s but you have to go in with the STAR system to turn it on with the US cars. Must have been too many false positive error message-induced visits to a dealer in the states. It's in my owners manual for Canadian versions only.

Glyn M Ruck

OK ^

Rudeney

Correct - for the ESP-based TPMS on the W209, it has to be enabled in SDS. There is no user-selectable option on the MFD menus.

BTW, i just had new rear tires put on this afternoon (Michelin Pilot Sport A/S). The guy at Costco tried selling me the TPMS maintenance package and I told him I don't have it. He said that all MY2006+ do, but then we discussed MBZs implementation. We then talked a bit about my dislike for TPMS and he agreed that he was really aggravated by some oversensitive system on his cars that trigger at 1psi below the set pressure. My wife's Jeep does this - it's alerting her because the right rear is down 1psi. At least it shoes individual tire pressures unlike some dumb system that just have a single indicator light.

Glyn M Ruck

Please listen to Rudeney for US cars. He knows their peculiarities better than I do. My comments relate to international cars where it is a menu item.

Rudeney

Yes, there are many differences in options and requirements for different markets. For example, here in the USA, somehow MBZ got out of the TPMS requirements for a few extra years. And there are things that are not even available here, like the speed limiter option.