I have a 99 Coupe that I purchased about 2 weeks ago. The Service TPS message appears when starting the car. The previous owner stated that the sensors were replaced about 12k miles ago along with a new set of GY Run Flats. He stated that a few days after the tires were installed, both driver side front and rear tires showed no reading and the TPS message was on. He set up a service appointment, but they started working again so he just let it go. The car is now doing the same thing, the same two wheels on the same side are not registering. He felt it could possibly be the "box". I'm new at TPS and would appreciate any input. Thanks.

 

I would try to reprogram the sensors first. Their is a tech tips thread on how to do it. Basically you go into the configuration on the dash by pressing a sequence of buttons and then take a large magnet (I used an old car speaker) and go around to each tire until the horn honks on all 4.

 

You may need to reset your TPMs. 1) Turn ignition on 2) Press "Reset" button in order to clear any IPC display warning messages 3) Press and release the "Options" button on the DIC to scroll through the display options until the IPC display is blank 4) Press and hold the DIC "Reset" button for 3 seconds 5) Press the "Options" button again until TIRE TRAINING message appears 6) Press "Reset" button until the IPC "Learn L Front Tire" message appears in order to begin the programming 7) Install the J41760 Tire Pressure Monitor (TPM) System Programming Tool (large magnet will do) over the left front valve stem 8) The horn will sound, indicating the left front TPM sensor is programmed (if this takes more than 15 seconds, pull magnet back and try again, it will give you three tries. Then you must start over) 9) When the horn sounds, proceed to program the next TPM sensor in the following order as directed by the IPC messages: -Learn R Front Tire -Learn R Rear Tire -Learn L Rear Tire Programming can be canceled by turning ignition off, waiting 2 minutes with no sensors being learned, finishing all 4 wheels or through the DIC. If the programming is canceled with less than 4 sensors learned, it will only accept the codes programmed up to that point.

 

Thanks for the info. I'm going to get a magnet and get started. I'll post the outcome soon.