FORD 2002 Thunderbird v.1 - Manual (Page 207)

Severe climates
If you drive in extremely cold climates (less than –36° C [–34° F]), it
may be necessary to increase the coolant concentration above 50%.
Refer to the chart on the coolant container to ensure the coolant
concentration in your vehicle will provide adequate freeze protection.
Never increase the engine coolant concentration above 60%
(protection to –60°F). At a level over 60%, your engine could overheat
and become damaged.
If you drive in extremely hot climates, it is still necessary to maintain the
coolant concentration at 50/50 coolant and water. Do not allow the
coolant concentration to fall below 40% coolant. At a concentration
less than 40%, the corrosion protection to your engine and cooling
components may be compromised and permanent damage may result.
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
symbol will
illuminate.
• The
symbol 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 and the engine
will completely shut down, causing steering and braking effort to increase.
H
C
Maintenance and specifications
207