Polaris Sportsman 850 Touring EPS, Service Manual, Page: 286 / 510

7.30
OPERATION
The AWD switch may be turned on or off while the
vehicle is moving, however, AWD will not enable until the
engine RPM drops below 3100. Once the AWD is
enabled, it remains enabled until the switch is turned off.
Engage the AWD switch before getting into conditions
where the front wheel drive may be needed. If the rear
wheels are spinning, release the throttle before switching
to AWD.
CAUTION
Switching to AWD while the rear wheels are spinning
may cause severe drive shaft and gearcase damage.
Always switch to AWD while the rear wheels have
traction or are at rest.
With the AWD switch off, the vehicle drives through the
rear wheels only (2 wheel drive). When the AWD is
enabled, the front drive acts as an on-demand AWD
system. This means, the front drive will engage once the
rear wheels have lost traction, and will remain engaged
until the torque requirement goes away (i.e. rear wheels
regain traction).
AWD Engagement: When the AWD switch is activated,
the AWD coil is powered by a 12 Vdc input which creates
a magnetic field. This magnetic field attracts an armature
plate that is keyed to the roll cage. When the ring gear
and roll cage are spinning (vehicle is moving), the
energized coil and armature plate will apply drag to the
roll cage that indexes the rollers inside the ring gear to an
engagement position. While in the engagement position,
the front drive will be in an “over-running” condition (not
engaged), until the rear wheels lose traction. Once the
rear wheels begin to lose traction, the front drive will
engage by coupling the output hubs to the ring gear via
the rollers. The front drive will remain engaged until the
torque requirement goes away (i. e. rear wheels regain
traction).
CAUTION
If the rear wheels are spinning, release the throttle
before turning the AWD switch on. If AWD is engaged
while the wheels are spinning, severe drive shaft and
clutch damage could result.
AWD Disengagement: Once the rear wheels regain
traction, the front wheels will return to the “over-running”
condition. The vehicle is now back to rear wheel drive
until the next loss of rear wheel traction occurs.
FINAL DRIVE