The speedometer may stop functioning with code P0722 stored in the powertrain control module (PCM). This may be caused by a worn speedometer gear due to coolant contamination of the transmission fluid. If contamination is found the radiator is most likely at fault. The transmission should also be thoroughly inspected and repaired or replaced as required.Google+
Car Problem Reports
Pontiac G3 Speedometer Not Working and/or Code P0722 Stored in PCM
Pontiac G3 Problem
Model Years Affected: 2009, 2010
Average Mileage: 63,000 mi (60,000 mi - 67,000 mi)
Visitor, 2009 Pontiac G3, 67,000 mi
The dealership contacted me saying that the coolant fluid has leaked into the transmission. Resulting in replacing both the transmission and the radiator. Total cost for repair is over $4,000 on an estimated value $6,000 car. I am not a happy camper and am quite disappointed that neither of those are covered under the warranty. I am currently considering my options and am leaning towards getting rid of the car and doing no further business with GM.
.... had to replace radiator (not covered) and transmission! over 60k miles this failure voids the power train warranty on the transmission, and is all out of pocket
the speedometer is not working, nor the odometer. A few months ago I had transmission contamination, but got it fixed. My tpms is also acting strange.