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
red (hot) area and: The coolant temperature warning
light will illuminate.
The service engine soon indicator
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 and 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 WARNINGS
Fail-safe mode is for use during
emergencies only. Operate the vehicle
in fail-safe mode only as long as necessary
to bring the vehicle to rest in a safe location
and seek immediate repairs. When in fail-safe
mode, the vehicle will have limited power,
will not be able to maintain high-speed WARNINGS
operation, and may completely shut down
without warning, potentially losing engine
power, power steering assist, and power
brake assist, which may increase the
possibility of a crash resulting in serious
injury. Never remove the coolant reservoir
cap while the engine is running or hot.
Note:
Driving the vehicle without repairing
the engine problem increases the chance of
engine damage. Take your vehicle to an
authorized dealer as soon as possible.
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.
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MKZ Hybrid (), enUSA Maintenance
