GMC 2006 DURAMAX Manual page 7

The high idle speed will be temporarily interrupted
and the engine speed will return to normal if any of
the following conditions occur:
•
The brake pedal is applied.
•
The accelerator pedal is pressed.
•
The automatic transmission is shifted out of
PARK (P) or NEUTRAL (N).
•
The clutch pedal on the manual transmission is
pressed (pickup models).
•
Vehicle speed is detected.
Once these inputs are removed, the engine idle speed
will slowly ramp back up to high idle after the normal
delay, if the conditions for engine coolant temperature
and air intake temperature are still met.
Manual High Idle System
(Van Models Only)
This system can be used to increase your engine idle
speed whenever the following conditions are met:
•
The brake pedal is not pressed.
•
The vehicle speed is below about 5 mph (8 km/h).
•
The transmission is in NEUTRAL (N) or PARK (P).
The manual high idle feature is activated by pressing
the switch on the instrument panel. When the switch is
pressed again, or any of the previous conditions are not
met, manual high idle will be deactivated. The manual
high idle has been preset at the factory. Your dealer may
change the setting to fit your needs.
If your vehicle has this
feature, the manual high
idle switch is located
on the instrument panel.
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