Ram Trucks 2014 3500 - Owner Manual - Manual (Page 381)

hard key a second time to turn off the Recirculation mode
LED and allow outside air into the vehicle.
NOTE: In cold weather, use of Recirculation mode may
lead to excessive window fogging. The recirculation
feature may be unavailable (soft-key button greyed out)
if conditions exist that could create fogging on the inside
of the windshield. On systems with Manual Climate
Controls, the recirculation mode is not allowed in Defrost
mode to improve window clearing operation. Recircula-
tion will be disabled automatically if this mode is se-
lected. Attempting to use Recirculation while in this
mode will cause the LED in the control button to blink
and then turn off.
Summer Operation
The engine cooling system must be protected with a
high-quality antifreeze coolant to provide proper corro-
sion protection and to protect against engine overheating.
OAT coolant (conforming to MS-12106) is recommended.
Refer to “Maintenance Procedures” in “Maintaining Your
Vehicle” for proper coolant selection.
Winter Operation
To ensure the best possible heater and defroster perfor-
mance, make sure the engine cooling system is function-
ing properly and the proper amount, type, and concen-
tration of coolant is used. Refer to “Maintenance
Procedures” in “Maintaining Your Vehicle” for proper
coolant selection. Use of the air Recirculation mode
during Winter months is not recommended because it
may cause window fogging.
Vacation/Storage
Any time you store your vehicle or keep it out of service
(i.e., vacation) for two weeks or more, run the air
conditioning system at idle for about five minutes in
fresh air with the blower setting in high. This will ensure
4
UNDERSTANDING YOUR INSTRUMENT PANEL 379