Acura 2011 RDX Owner's Manual page 379

Your vehicle has an electric vacuum
pump located in the engine
compartment. When you drive in
cold weather or thinner air at high
altitude, the electric vacuum pump
operates more frequently after the
engine is started.
When the electric vacuum pump is in
operation, it makes some mechanical
noises come from the engine
compartment. This is normal.
Check Starter System Message
U.S.
If there is a problem with the starter
system, you will see a ''CHECK
STARTER SYSTEM'' message on the
multi-information display when the
ignition switch is turned to the ON
(II) position. You will also see this
message when the auto control mode
of the starter system has a problem.
2011 RDX
Starting the Engine
Canada
If this message is on, the ignition
switch has to be held in the START
(III) position manually until the
engine starts. The ignition switch can
be held in that position up to 15
seconds.
Even though you may be able to start
the engine manually without the auto
control mode of the starter system,
have your dealer inspect your
vehicle.
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