Direct & Indirect Tire Monitoring systems: TPM/RDS & FTM/RPA

[Qsilver7]

Originally Posted by X5 Meister

....BMW has had TPM and FTM for years now and has gone back and forth between the technologies. In fact, in the past BMW preferred a FTM to a TPM... however this has changed due to run flats...

Just want to give a big thanks to X5 Meister for the chart in the quote above. It really helped relieve some fears I had today...along with the info below from the BMW TIS.

Hopefully the info in this post will help owners understand the different tire monitoring system their vehicles may have. I was unsure what the multiple acronyms meant...the direct tire pressure monitoring systems (TPM/RDS) versus the indirect (FTM/RPA) system...perhaps others are/were, too.

The direct TPM/RDS system uses a sensor mounted to the wheel that sends a wireless signal to the RDS component...the indirect FTM/RPA system relies on the cars ABS/DSC system (counts wheel revolutions).

I've only had my X5 for a little over 1 week, and I had winter tires installed this morning. Doing the final inspection I noticed that I had rubber valve stems instead of the metal ones that were originally on the car. I thought they had forgotten to install the tire pressure sensors...but the tire jockey claimed there weren't any installed on the wheels when he removed the tires.

Being in new territory, I said okay. Then when I got home, I thought to check the spare...and it had the metal valve stem & cap etc...this made me uneasy. So off to the forum for a search as to what models/model years may have been different and/or what the flat tire monitor system was all about.

Well, I found the info in the quote above, as well as the info from the TIS below...and sure enough...my X5 has the FTM (flat tire monitoring) system that uses the ABS sensor...so I wasn't going to be losing a feature and getting a warning light.

If I was confused by this, I'm sure others may be or have been, too. So just to clarify for anyone searching...you can see the info in this post that may help you know what's installed on your X5.