2006 Mercury Grand Marquis Owner Guide 2nd Printing - Page 235

Maintenance and Specifications What you should know about fail-safe cooling If the engine coolant supply is depleted, this feature allows the vehicle to be driven temporarily before incremental component damage is incurred. The "fail-safe" distance depends on ambient temperatures, vehicle load and terrain. How fail-safe cooling works If the engine begins to overheat: • The engine coolant temperature gauge will move to the H (hot) area. • The Check Engine indicator light will illuminate. • The symbol will illuminate. If the engine reaches a preset over-temperature condition, the engine will automatically switch to alternating cylinder operation. Each disabled cylinder acts as an air pump and cools the engine. When this occurs the vehicle will still operate. However: • The engine power will be limited. • The air conditioning system will be disabled. Continued operation will increase the engine temperature: • The engine will completely shut down, causing steering and braking effort to increase. Once the engine temperature cools, the engine can be re-started. Take your vehicle to an authorized dealer as soon as possible to minimize engine damage. When fail-safe mode is activated You have limited engine power when in the fail-safe mode, so drive the vehicle with caution. The vehicle will not be able to maintain high-speed operation and the engine will run rough. Remember that the engine is capable of completely shutting down automatically to prevent engine damage, therefore: 1. Pull off the road as soon as safely possible and turn off the engine. 2. Arrange for the vehicle to be taken to an authorized dealer. 3. If this is not possible, wait a short period for the engine to cool. 4. Check the coolant level and replenish if low. Never remove the coolant reservoir cap while the engine is running or hot. 235 2006 Grand Marquis (grn) Owners Guide (post-2002-fmt) USA (fus)