2003 GMC Yukon Owner's Manual - Page 200

• If the Traction Assist System is affected by an anti-lock brake system, TAS or engine-related problem, the system will turn off and the light will come on. Have your vehicle serviced. • If the vehicle is driven over an extremely rough road, the system will turn off and the light will come on. The light will go off a few seconds after the rough road conditions go away or when the vehicle comes to a complete stop. This is normal operation. It also provides an indicator of how hard your vehicle is working. During a majority of the operation, the gage will read 210°F (100°C) or less. If you are pulling a load or going up hills, it is normal for the temperature to fluctuate and approach the 250°F (122°C) mark. If the gage reaches the 260°F (125°C) mark, it indicates that the cooling system is working beyond its capacity. See Engine Overheating on page 5-29. Transmission Temperature Gage Engine Coolant Temperature Gage United States United States Canada Canada Your vehicle may be equipped with a transmission temperature gage. This gage shows the engine coolant temperature. 3-46