1994 GMC Jimmy Owner's Manual - Page 214

If No Steam Is Coming FromYour Engine If you get the overheat warning but see hear no steam, the problem may or not be too serious. Sometimes the engine can get a little too hot when you: Climb a long hillon a hot day. Stop after high speed driving. 0 Idle for long periods in traffic. Tow a trailer. If you get the overheat warning with no sign of steam, try this a minute for or so: 1. If you have an air conditioner, turn it off. 2. Turn on your heater to full hot at the highest fan speed and open the window as necessary. 3. If you're in a trafficjam, shift to "N" (Neutral). If you no longer have the overheat warning, you can drive. Just safe, be to drive slower for about ten minutes.the warning doesn't come back on, If you can drive normally. If the warning continues, pull over, stop, and park your vehicle right away. is If there's still no sign of steam, push the accelerator until the engine speed about twiceas fast as normal idle speed. Bring the engine speed back to normal idle speed after two three minutes. Nowsee if the warning stops. or But then, if still have the warning, you TURN OFF THE ENGINEAND GET EVERYONEOUT OF THE VEHICLE until it cools down. You may decide not to the hood but to get service help right away. lift When you decide it's safe tolift the hood, here's what you'll see: A. Coolant recovery tank B B. Radiator pressure cap C. Engine fan If the coolant inside the coolant recovery tank is boiling, don't do anything else until it cools down. 5-12