Snowmobile Arctic Cat 2-Stroke (2007 year). Manual - part 63

4-26

FS025A

FUEL PRESSURE REGULATOR

The fuel pressure regulator is located in the fuel pump.

The fuel pressure regulator maintains the fuel pressure

at a constant specified level.

FS023A

FUEL PUMP CIRCUIT

The fuel pump and its circuit are provided with current

from the fuel pump coil on the stator.

FS024

For this circuit to function correctly, five components

must be in good working order.

Check the following components before considering

the fuel pump assembly to be defective.

A. Fuel pump coil - see coil test procedure.

B. Emergency stop switch and ignition switch

must be ON and in good working order.

C. Fuel pump - see fuel pump test procedure.

D. Wiring harness and connectors - clean the con-

nectors and test the harness.

E. ECU.

Self-Diagnostic

EFI System 

(800/1000 cc)

„NOTE: For testing the 800/1000 cc EFI system,
refer to the EFI Diagnostic System Manual (p/n
2257-850), which accompanies Laptop Diagnostic
Tool (p/n 0744-048) and Laptop Diagnostic Test Kit
(p/n 0744-050). 

Self-Diagnostic

EFI System 

(500/600 cc)

„NOTE: To aid in testing the 500/600 cc EFI sys-
tem, refer to the EFI Analyzer Usage Manual (p/n
2259-020), which accompanies EFI Analyzer Kit
(p/n 0744-049).

INTRODUCTION

The Electronic Control Unit (ECU) contains a built-in,

self-diagnostic system which detects trouble within the

sensor signal network and then flashes a code in the

check engine light in the speedometer/tachometer.

ZJ001B

The fuel system and the ignition system remain two

separate systems. In a no-start situation, first deter-

mine if the problem is caused by lack of spark or by a

fuel delivery problem or by an internal engine condi-

tion (low cylinder compression for example).

Using the EFI Ignition Analyzer, connect the test har-

ness to the ECU diagnostic connectors. Connect the

test harness red external lead to the positive terminal

of a 12-volt battery and connect the black external test

harness lead to the negative terminal.

4

4-27

If any of the circuits are faulty, a code will now be

flashed by the check engine light.

If no code is flashed, turn on the analyzer. Press the

MENU SELECT buttons until the words KOKUSAN

appear on the display; then press the TEST button. The

analyzer is now programmed for testing the Arctic Cat

EFI System.

Using the MENU SELECT buttons, press the button

repeatedly until Memory Problem Diagnosis Test

appears on the display; then press the TEST button. If

any sensors have intermittent problems, they will be

indicated on the display.

The code flashed from the check engine light will first

be a number of flashes. Count the number of flashes

and refer to the appropriate Diagnostic Codes in Sec-

tion 1. The code repeats itself with approximately a 2-

second delay between each series of flashes.

„NOTE: When reading the check engine light
flash sequence, have paper and pencil available to
write down the codes being flashed. More than one
code may be flashed.

Once the problem area has been determined, check the

components involved using the Fluke Model 73 Multi-

meter (p/n 0644-191) or the EFI Analyzer (p/n 0644-

476) depending on which test is being made.

Diagnostic Codes

(500/600 cc)

TROUBLESHOOTING INDIVIDUAL 

COMPONENTS

„NOTE: With the Arctic Cat EFI System, it is
extremely important that the ECU receives the
proper current output from four coils (two charge
coils, an injector coil, and a fuel pump coil) to
function as designed. If a problem exists, these
coils should be checked using the following proce-
dures.

Charge Coil (1)/Charge Coil (2) 
Resistance Test

The charge coils power the ECU. To test these coils,

disconnect the 3-wire connector from the ECU to the

stator.

1. Set the meter selector to the OHMS scale and test

between the black/red and green/red wires (coil 1).

2. The meter must show 7.20-10.8 ohms. 

3. Test between the green/red and brown/white wires

(coil 2). 

4. The meter must show 7.20-10.8 ohms.

„NOTE: If either test is not within specifications,
the stator must be replaced. Refer to the wiring
diagram.

Injector Coil Resistance Test

The injector coil located on the stator powers the two

injectors.

1. Disconnect the double-wire plug with two blue/

white leads from the stator to the ECU.

2. Set the meter selector to the OHMS scale.

3. Connect a meter lead to each of the blue/white

leads. The meter must show 15.2-22.8 ohms.

„NOTE: If reading is not within the specification,
recheck to confirm test results. If still out of toler-
ance, replace the stator.

„NOTE: If the resistance test is good, a peak
reading voltage test should also be made. Refer to
Peak Voltage Tests and Specifications in this sub-
section.

Fuel Pump Coil Resistance Test

The fuel pump coil powers the fuel pump through the

ECU.

„NOTE: With the engine running, there should
12.3-12.9 DC volts supplied to the fuel pump for
operation. To test fuel pump coil resistance, use
the following procedure.

1. Disconnect the double-plug with the two orange

wires from the ECU.

2. Set the meter selector to the OHMS scale. Connect

a meter lead to each of the two orange leads.

3. The meter must show 1.52-2.28 ohms.

„NOTE: If reading is out of tolerance, recheck to
confirm reading. If still out of tolerance, replace
the stator.

„NOTE: If the resistance test is good, a peak
reading voltage test should also be made. Refer to
Peak Voltage Tests and Specifications in this sub-
section.

Lighting Coil Resistance Test

The lighting coil located on the stator provides AC

power to the lighting system and accessories through

the chassis control unit. To test the lighting coil resis-

tance, follow this procedure.

1. Disconnect the 3-wire connector at the engine.

2. Set the meter selector to the OHMS scale.

3. Test between the two yellow leads.

4-28

4. The meter must show 0.8-0.12 ohm.

„NOTE: If reading is out of tolerance, recheck to
confirm reading. If still out of tolerance, replace
the stator.

ECU 

(500/600 cc)

ACTIVATING ECU MEMORY

The ECU has a self-diagnostic mode built into the unit.

It is a very valuable tool in troubleshooting. Once the

problem area code has been flashed by the check

engine light in the speedometer/tachometer, follow the

troubleshooting procedure in this sub-section.

The ECU also has a memory mode for determining if

any of the five sensors have intermittently failed. To

activate the memory system, follow these steps.

1. Connect the analyzer test harness to the ECU diag-

nostic connector.

2. Connect the analyzer test harness red and black

leads to a 12-volt battery.

3. Turn the analyzer switch ON.

4. Press the analyzer MENU SELECT buttons

repeatedly until KOKUSAN appears on the dis-

play. Once the word KOKUSAN appears on the

display, press the TEST button. The analyzer is

now set up to test the EFI system.

5. Press the analyzer MENU SELECT buttons

repeatedly until the words Memory Problem Diag-

nosis Test appears on the display.

6. Press the analyzer TEST button. If all sensors are

good, SENSORS ALL O.K. will appear on the

display. If any of the sensors have intermittently

failed or are faulty, they will appear on the display.

Proceed then to checking the faulty sensor individ-

ually as covered in this section.

„NOTE: Once problem areas have been deter-
mined, always check the component(s) for clean
and tight connections.

7. To erase the memory of the ECU, press the TEST

button once again; then push the MENU SELECT

buttons until Diagnosis Memory Clear appears on

the display. Turn the analyzer OFF and then back

ON again. Reselect KOKUSAN mode; then pro-

ceed to the Memory Problem Diagnosis Test and

push the TEST button. The display should indicate

SENSORS ALL O.K. which indicates the memory

has been cleared.

REMOVING

1. Disconnect the wiring harness lead from the ECU.

2. Remove the two screws securing the ECU to the

air-intake silencer (Crossfire/M-Series) or to the

left-front upper frame (F-Series).

3. Remove the ECU.

INSTALLING

1. Secure the ECU to the air-intake silencer (Cross-

fire/M-Series) or to the left-front upper frame (F-

Series) with the screws.

„NOTE: On the Crossfire/M-Series, make sure the
diagnostic connector plug faces the oil reservoir.

2. Connect the wiring harness to the ECU.

„NOTE: Make sure all connectors are clean and
tight. Apply dielectric grease to all connectors.

Testing Individual 

Components

„NOTE: For individual resistance testing proce-
dures, see Section 5 in this manual.

„NOTE: For the following tests, use the Fluke
Model 73 Multimeter (p/n 0644-191) or a multimeter
of the same quality.

THROTTLE POSITION SENSOR 

If the snowmobile is under warranty, the throttle posi-

tion sensor on the EFI system is not a serviceable part.

If the sensor should malfunction, the complete throttle

body assembly must be replaced.

„NOTE: If the snowmobile is in warranty, break-
ing the seal on the idle screw jam nut or the Phil-
lips-head screws on the TPS will void warranty.

„NOTE: It is important to order a throttle body
assembly with the same symbol marking on the
injectors as the ones being replaced. The symbol
is located on the side of the injector top.

Memory Problem Diagnosis Test

4

4-29

FUEL INJECTORS

FS021

Testing Resistance

1. Disconnect the fuel injector wiring harness.

2. Set the meter selector to the OHMS scale.

3. Test between the two injector terminals. Test spec-

ification is 2.4-3.3 ohms.

CM039

4. If not within specifications, replace the injector.

Removing

1. Loosen the clamp securing the fuel supply hose to

the fuel rail; then remove the hose from the fuel

rail.

2. Disconnect the wiring harness from each injector.

3. Remove the screws securing the injector hold-

down plate to the throttle body assembly; then

remove the plate from the injectors.

4. Remove the fuel injectors from the throttle body/

intake manifold assembly.

CM203A

Installing

1. Apply a light coat of oil to all O-rings; then install

the upper and lower O-rings onto each injector.

2. Install the injectors into the throttle body assem-

bly.

3. Place the injector hold-down plate into position on

top of the injectors and secure with two screws.

4. Connect the fuel delivery hose to the fuel rail and

secure with a clamp.

„NOTE: When securing the fuel delivery hose,
position the clamp as shown.

0729-325

5. Connect the wiring harness to the injectors making

sure the number 1 harness is connected to the

MAG-side injector.

! CAUTION

The fuel supply hose may be under pressure. Place
an absorbent towel around the connection to absorb
fuel; then remove the hose slowly to release the
pressure.