Originally Posted by ELP_JC
The TPMS system changed dramatically in 2010, I believe. It went from 4 receivers to a central one. In many cars the owner can reset them and in 2 or 3 miles it's reprogrammed. Does anybody know out of curiosity how 2012 cars work?
GM did change the TPMS computer in the car (actually a section of the RCDLR module) in 2010, but it was a very minor, simple change.
The only thing that changed in 2010 was to a different TPMS computer in the car that uses a different tire pressure sensor.
If you look on the RPO code list in the glove compartment of your car, you'll see the TPMS computer that's in your car listed there:
- 2005-2009 - "UJ9" (UH3 for cars built for foreign delivery, and that TPMS uses a different sensor that transmits on a foreign approved frequency)
- 2010 plus - "UJM" (which has been used in several models like the Impala and Malibu for several years prior to being put into the C6).
I don't know why they changed, because one TPMS doesn't do anything different at all from the other one!!
However, the sensors
did operate a little differently.
Actually, the sensors that came in the very early 2005 C6 were the same ones used in the '04 Cadillac XLR, and they could be triggered with a magnet during the programming procedure. For all C6's built after about Sept 2004 GM/Chevy discontinued those sensors and the only ones available are the current 2005-2009 sensors - a gray sensor with GM Part# 25758220 (you might be able to make out that # molded into the case of the sensor):
That 2005-2009 sensor above can only be triggered by the 125 kHz transmission from a TPMS tool.
In 2010 they changed to the UJM TPMS computer and that computer only works with a green sensor with GM Part# 15268606 (at least in the beginning!!):
The good thing about the green 15268606 sensor above is that during the programming procedure it could be triggered by a TPMS tool or by changing air pressure in the tire!!
However, in Jan 2011 they changed the sensor again - same TPMS, just started installing a black sensor with GM Part# 20925924:
So....any 2010 C6, and any 2011 built through December 2010 should have the green sensors installed by the factory during build.
Any C6 built from January 2011 on should have the black sensor installed when being built.
They have the same TPMS computer (UJM), either sensor will work, but the only sensor readily available in the GM parts system should be the black one - unless some of the green may still be floating around and available until gone.
The green one could be triggered by changing air pressure in the tire, and when a dealership was programming the green sensors in your C6 (also used in several Chevy models), once your C6 was put into the "learn mode" it would pick up the first sensor signals it received, and if a tech working on another car (Malibu, Impala, etc.) in the shop and adjusted the tire pressure on the other car, the TPMS in your C6 would log the other car's sensor into the C6 TPMS!!
To avoid that happening, in Jan 2011 GM discontinued the green sensor and began using the black sensor. The black sensor can only be triggered to send out its data during the programming procedure by a TPMS tool
So....that's the only difference between the 2005-2009 and the 2010+. They use different TPMS computers that require different tire pressure sensors. You must use sensors for either the UJ9 or UJM TPMS in your year model - the other part# sensors just won't work because they transmit a different digitized data string that only is recognized by the TPMS computer that is compatible with them.
The 2010+ can use either the black sensors, or the green ones if you can still find any in the GM parts system or get used ones.
Edited 12/14/2013: Actually, I have discovered that the 2010+ sensors for the UJM TPMS computer do have an additional feature not found in the 2005-2009 sensors.
The 2010+ sensors detect the temperature in the tire. The DIC doesn't display the temp, but if you have a TPMS tool that has a screen that displays the data transmitted by the sensor, then you'll see the temp displayed.
Below is a picture of the info displayed on my OTC 3833 TPMS tool when I did a diagnostic check of a sensor in a GS wheel after it came off the track after about 25 minutes of hard running at Sebring.
After the "Temp", the sensors in a 2005-2009 just have a series of dashes. However, you can see below that the 2010+ sensors show the temp in degrees F.
The temp has increased from ambient to 185 degrees, and that has increased the pressure from about 30 psi cold to the 36 psi displayed: