Snowmobile Polaris 2006 - 2007 FS / FST. Manual - part 18

4.13

EFI / Ignition Systems

4

Rev. 1 07/2006

Engine RPM / Vehicle Speed Limit Modes

The engine management system will limit engine RPM or
vehicle speed if the following conditions are encountered.

Turbo Boost Reduction Modes

The engine management system will reduce turbo boost to base
boost (ambient pressure + 400 mbar) if the following
condition(s) are encountered:

• The engine temperature overheat MIL lamp is 

illuminated.

• Engine coolant temperature is at or below 122

° F (50° 

C) OR at or above 203

° F (95° C).

• Intake manifold air temperature is at or below 32

° F (0° 

C) OR at or above 158

° F (70° C).

• ECU knock control reduces ignition timing by -6

° 

above 5000 RPM.

• Over-boost condition occurs.

• Fuel Pump Octane Number (PON) is not adequate. Use 

Premium 91, 92, 93 PON fuel for maximum engine 
performance.

RPM / Vehicle Speed Limit Modes

C

ONDITION

RPM / V

EHICLE

 S

PEED

 L

IMIT

Idle Speed (Engine @ Operating Temperature)

1450

± 200 RPM (FS)

1550

± 200 RPM (FST)

Recommended Operating RPM (WOT - Shift Out Speed)

8000 - 8100 RPM

Maximum Engine Speed (Fuel Cutoff)

8800 RPM

Perc 4 Reverse Upper RPM Engagement Limit

2500 RPM / 0 MPH

Perc 4 Reverse Engaged - Vehicle Speed Sensor Working

11 MPH (18 km/h)

Perc 4 Reverse Engaged - Vehicle Speed Sensor Not Working

5300 RPM

Rollover Switch Error - Vehicle Speed Sensor Working

37 MPH (60 km/h)

Rollover Switch Error - Vehicle Speed Sensor Not Working

6000 RPM

Throttle System Stuck - Lever @ Idle (Closed) Position

2400 RPM

Throttle System Stuck - Lever @ Off Idle Position - Vehicle Speed Sensor 
Working

18 MPH (30 km/h)

Throttle System Stuck - Lever @ Off Idle Position - Vehicle Speed Sensor Not 
Working

5450 RPM

4.14

EFI / Ignition Systems

Rev. 1 07/2006

Fuel Injection Circuit

The fuel injection circuit and fuel injectors are responsible for
delivering fuel to each combustion chamber. Power to each
injector is supplied by the EFI relay and protected by a 20A fuse.
The ECU controls each injector by switching each circuit to

ground. The time and duration the ECU grounds each circuit
determines the injection timing and pulse width.

NOTE:  FS Fuel Injector Color = Orange

FST Fuel Injector Color = Black

4.15

EFI / Ignition Systems

4

Rev. 1 07/2006

Ignition Coil Circuit

The ignition coil circuit and ignition coils are responsible for
providing spark energy to the spark plugs. Power to each
ignition coil is supplied by the ignition relay. The EFI relay
supplies power to the ignition relay via a 20A fuse-protected
circuit. The ECU controls each ignition coil by opening each

control circuit, thus collapsing the field inside each coil. The
secondary coil within each coil pack is diode protected to
prevent activation arcing when the ECU closes each control
circuit. The diode prevents testing the secondary coil with an
ohmmeter.

4.16

EFI / Ignition Systems

Rev. 1 07/2006

Throttle Position Sensor Circuit (TPS)

The throttle position sensor (TPS) is responsible for converting
the mechanical action of the throttle plates into an analog signal.
The ECU uses this signal to determine the position of the throttle

plates and therefore the operator’s demand for more or less
engine torque.

All three circuits that connect to the TPS are supplied and
monitored by the ECU. The TPS is located on the throttle body
assembly.