You have 2 different problems, resetting the tire pressure has nothing to do with the speedometer. Been having alot of problems with the ipc's on these vehicles. As far as the tire pressure monitor it might have to be relearned or you might have a tpm sensor or sensors bad. Here is a bulletin to reference. Some customers of 2003-2004 model year Cadillac Escalade, Escalade ESV, and Escalade EXT; Chevrolet Avalanche, Silverado, Suburban, and Tahoe; and GMC Sierra, Yukon, and Yukon XL vehicles have reported that one or more of the instrument panel (IP) cluster gauges stick, flutter, or become inoperative. This may cause inaccurate readings, including the speedometer and fuel gauge.
This special coverage covers the condition described above for a period of 7 years or 70,000 miles (110,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership.
Dealers are to replace the instrument panel cluster after the condition has been verified. The repairs will be made at no charge to the customer.
This might help.
Wednesday, February 27th, 2008 AT 8:24 PM