2003 TPMS control module location?

 

I suspect this is not just a curiosity, but rather that you are getting the "TPMS Module Failure" message.
I have received it several times and I could usually clear it by resetting the TPMS system from the steering wheel button menus. Once I had to replace a TPMS sensor in a wheel.
If you are having trouble resetting it from the menus (or COMAND?), have a tire shop check that each TPMS wheel sensor is working and has a good battery. Some mechanics will have an appropriate TPMS tool too.
A tire shop will likely charge about $100 to replace one TPMS sensor; some independent mechanics might charge less.

 

Thank you for replying. I had all the tire sensors placed because one had failed. The tire shop tried several times to reprogram the new sensors but couldn’t. Advised me that there was something else wrong and probably the control unit.

 

You say that one TPMS wheel sensor failed and you then had all replaced (which is a good idea).
That tells me the TPMS control module was working when the first wheel sensor failed. Seems unlikely it then failed during a period of a few weeks after working for 20+ years.
I'm not a TPMS expert, but I own two auto repair shops; one specializes in aftermarket wheels and tires and we obviously install a lot of TPMS sensors.
It is very unlikely the tire shop used genuine MB sensor as they are likely $150 each. Instead they use "generic" sensors and then programmed them with a tool. Our shop does this too as the generic sensors in bulk are about $15 each. We have gone through various brands of sensors and various TPMS programming tools. The first tool was about $250, then we bought a better tool for $600 and most recently a SnapOn TPMS tool for $2500. I don't understand how this programming works, but some vehicles are fussy and need the fancy TPMS tool which connects to the OBD2 port to talk to the modules at the same time as it programs the wheel sensors.
In short, your tire shop may not have had the correct tool to program generic TPMS wheel sensors to an SL500.
OR, the TPMS control module did actually fail. I see them on eBay for around $80.
I will check on Monday at my shop to learn what is needed to program a wheel sensor on my SL600; I know we have replaced one so far.

 

I appreciate your reply. I would like to get help on locating the control unit just to inspect it and try to chance down the problem. Any direction would be appreciated.

 

Not wanting to deal with this on my 2009 SL550, I had my Indie "deprogram" TPMS out as "not present" - I look at my tires daily as I drive the car and somehow survive driving my air cooled Porsche without this feature. Cheers Socks

 

Tire sensors bought from tirerack dot com always work fine and cost about $84 each. There are different frequency sensors, I wonder if that shop installed wrong frequency sensors? Your car requires the 315 Mhz sensors.