Polaris Trail Blazer Service Manual page 614

ELECTRICAL
Speedometer System, Electronic
Electronic Speedometer Troubleshooting Overview of Operation
The Polaris Electronic ATV speedometer is powered by
battery voltage (12 VDC) and requires engine RPM,
transmission gear, and wheel speed sensor input signals
for proper operation. Wiring to the speedometer head
consists of a three-pin connector from the wheel speed
sensor and a six-pin connector from the main ATV wiring
harness.
A non-serviceable internal memory battery maintains
odometer and hour meter data when the machine is not
running.
The illumination lamp inside the gauge is non-service-
able and is designed to last for the life of the unit.
In addition to the ground speed in Miles Per Hour (MPH)
or Kilometers Per Hour (KPH), odometer, and trip odom-
eter, the electronic speedometer provides the following
functions:
S Records Engine Run Time in Hours
S Reverse Speed Limit - (Polaris Variable Transmission
[PVT] models only)
S Prevents AWD engagement: When engine RPM
is too high
Vehicle Speed and Odometer
An electronic wheel speed sensor located on the right
front brake caliper bracket senses vehicle speed. The sen-
sor "reads" notches in the rotating brake rotor (disc) and
sends a signal through the three-pin harness pin B. The
wheel speed sensor receives approximately 10 VDC pow-
er from the speedometer head and does not differentiate
between forward and reverse wheel rotation. LED Test
Light PN 2871745 can be used to quickly test the sensor.
INPUTS
Transmission
Switch
Alternator RPM Signal
Wheel Speed Signal
Polaris Sales Inc.
GRY/OR
B
F
YEL/RED
D
Speedometer
Engine Run Time Hour Meter
If the engine is running, the hour meter is recording the
run time. The hour meter (RPM) signal comes from the
stator to the speedometer on pin D (typically the yellow/
red wire).
Reverse Speed Limit (PVT models only)
The transmission gear signal is sent to the speedometer on
pin F. The operating speed of the ATV is limited when the
transmission is shifted into reverse gear. The ignition
spark to the engine is turned off if the ground speed ex-
ceeds 7 to 9 MPH in reverse gear. Ignition spark returns
when the vehicle speed drops below 7 MPH in reverse.
NOTE: If the speedometer does not detect a wheel speed
sensor (motion of the front wheel) it will limit RPM to
approximately 3600 in reverse.
High RPM AWD Hub Engagement Disable
The electronic speedometer prevents AWD engagement
at high RPM. If engine RPM is above 3000, the ground
connection for the AWD wheel coils and AWD indicator
lamp (Pin E) is not supplied by the speedometer.
The engine RPM signal is sent to the speedometer on Pin
D (typically the yellow/red wire). It is important to note
that a failed voltage regulator can prevent AWD engage-
ment.
Override Button (PVT models only)
The override button (on the left handlebar switch block)
interrupts the transmission gear signal allowing AWD
engagement in reverse as long as the override button is
depressed.
Refer to the flowcharts and schematic diagrams to trou-
bleshoot the electronic speedometer.
BRN/WHT
A
E
C
BLK
10.45
OUTPUT
AWD Wheel Coils
Engine Stop Signal
(CDI Box)
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