Volvo VHD - Manual (Page 237)

Brakes 231
There is also an engine shut-down device
in the EECU that shuts the engine down af-
ter a pre-programmed time in order to save
fuel. This is activated when the yellow
parking brake knob is pulled out. There-
fore, some drivers park and release the
parking brakes using only the red knob to
keep the engine running. It is then easily
overlooked that in a vehicle parked with
both the yellow and red knobs activated,
only the red knob is pushed in by habit.
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