Jeep Grand Cherokee Operating Information Manual page 299

HDC has three states:
1. Off (feature is not enabled and will not acti-
vate).
2. Enabled (feature is enabled and ready but
activation conditions are not met, or driver is
actively overriding with brake or throttle ap-
plication).
3. Active (feature is enabled and actively con-
trolling vehicle speed).
Enabling HDC
HDC is enabled by pushing the HDC switch, but
the following conditions must also be met to
enable HDC:
• Driveline is in 4WD Low Range
• Vehicle speed is below 5 mph (8 km/h).
• Parking brake is released.
• Driver door is closed.
Activating HDC
Once HDC is enabled, it will activate automati-
cally if driven down a grade of sufficient magni-
tude. The set speed for HDC is selectable by
the driver, and can be adjusted by using the
gear shift +/-. The following summarizes the
HDC set speeds:
HDC Target Set Speeds
• P = No set speed. HDC may be enabled but
will not activate
• R = 0.6 mph (1 km/h)
• N = 1.2 mph (2 km/h)
• D = 0.6 mph (1 km/h)
• 1st = 0.6 mph (1 km/h)
• 2nd = 1.2 mph (2 km/h)
• 3rd = 1.8 mph (3 km/h)
• 4th = 2.5 mph (4 km/h)
• 5th = 3.1 mph (5 km/h)
• 6th = 3.7 mph (6 km/h)
• 7th = 4.3 mph (7 km/h)
• 8th = 5.0 mph (8 km/h)
• 9th = 5.6 mph (9 km/h) – If Equipped
NOTE:
During HDC, the +/- shifter input is used for
HDC target speed selection but will not af-
fect the gear chosen by the transmission.
When actively controlling HDC, the trans-
mission will shift appropriately for the
driver-selected set speed and correspond-
ing driving conditions.
Driver Override
The driver may override HDC activation with
throttle or brake application at anytime.
Deactivating HDC
HDC will be deactivated but remain available if
any of the following conditions occur:
• Driver overrides HDC set speed with throttle
or brake application.
• Vehicle speed exceeds 20 mph (32 km/h) but
remains below 40 mph (64 km/h).
• Vehicle is on a downhill grade of insufficient
magnitude, is on level ground, or is on an
uphill grade.
• Vehicle is shifted to park.
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