Snowmobile Arctic Cat (2002 year). Manual - part 74

5-15

5

Testing Ignition System

(EFI Models)

„

NOTE: There must be free-play between the

throttle lever and the control housing.

MAIN WIRING AND SAFETY 

SWITCHES

1. Check the wiring connections coming from the

ignition key and emergency stop switches. The

throttle control switch connector is located on the

front side of the steering post. If any of the

connections appear dirty or corroded, clean them

with fine sandpaper and compressed air; then

connect all wires and squeeze the connections with

a pliers for additional tightness.

2. Disconnect the main wiring harness connector

coming from the engine stator assembly.

Disconnecting this connector will bypass the main

wiring harness and all switches which will not

allow the engine to be shut off without first

installing an additional auxiliary ground wire.

3. Insert an auxiliary ground wire into the black wire

of the four-wire main harness connector on the

engine side. To stop the engine once it has been

started, touch the auxiliary ground wire to the

engine.

4. Support the rear of the snowmobile up on a

shielded safety stand; then set the brake lever lock.

Inspect the complete throttle mechanism to assure

that it's working properly.

5. Attempt to start the engine. To stop the engine (if

the engine starts), touch the auxiliary ground wire

installed into the four-wire connector to a ground

on the engine. If the engine fails to start, the

problem is with the coils mounted on the engine,

high tension coil assembly, or the ECU. If the

engine starts, the problem is with the switches,

main wiring harness, or throttle cable free-play.

IGNITION KEY SWITCH

1. Disconnect the ignition key switch connectors;

then connect the ohmmeter leads to each of the

ignition key switch terminals.

2. With the switch in the OFF position, the meter

must read less than 1 ohm of resistance.

3. With the switch in the ON position, the meter must

read OL (infinite resistance).

THROTTLE CONTROL SWITCH

1. Verify that the throttle cable has free-play between

the throttle lever and control housing.

2. Disconnect the throttle control switch connector;

then connect one ohmmeter lead to the brown wire

and the other lead to the black/white wire of the

emergency stop switch.

3. With the throttle lever in the idle position and the

emergency stop knob in the up (RUN) position,

the meter must read no resistance (open). If the

meter reads resistance (closed), replace the switch.

4. With the throttle lever in the idle position and the

emergency stop knob in the down (STOP)

position, the meter must read resistance (closed).

If the meter reads no resistance (open), replace the

switch. With the emergency stop knob still in the

down (STOP) position, move the throttle lever to

the wide open position. The meter must read no

resistance (open). If the meter reads resistance

(closed), replace the switch.

5. Connect one ohmmeter lead to the brown wire and

the other lead to the violet wire. With the

emergency stop knob in the down (STOP)

position, the meter must read resistance (closed).

If the meter reads no resistance (open), replace the

switch. With the emergency stop knob in the up

(RUN) position, the meter must read no resistance

(open). If the meter reads resistance (closed),

replace the switch.

Troubleshooting 

Ignition System

(Fan Cooled Models)

When troubleshooting the standard “normally open”

ignition system, use the following procedure.

1. Remove the spark plugs and visually check their

condition. Replace any fouled plug. Attach the

spark plugs to the high tension leads and ground

them on the cylinder heads.

„

NOTE: Make sure the ignition switch and the

emergency stop switch are in the ON position.

! CAUTION

Before checking for spark, place all the engine
switches in the deactivated position. In the event
the engine could be flooded, pull the starter rope
(slowly at first) several times to clear the engine
of excess fuel.

! CAUTION

Never crank the engine over without grounding
the spark plugs. Damage to coils and/or CDI unit
may result.

5-16

2. Crank the engine over and check for spark. If no

spark is present, check to make sure the throttle

cable is properly tensioned. Compress the throttle

control and while holding the throttle control in

this position, crank the engine over and check for

spark. If spark is now present, adjust the throttle

cable tension.

„

NOTE: On all models, there must be 0.75-1.5 mm

(0.030-0.060 in.) free-play between the throttle
lever and the control housing.

733-081C

3. If no spark is present, disconnect the main wiring

harness from the engine. Crank the engine over. If

spark is present, the problem is either one or more

of the following.
A. Defective emergency stop switch

B. Defective safety switch in throttle-control

housing

C. Grounded or shorted wire connection at the

throttle-control housing or main wiring harness

D. Defective ignition switch

„

NOTE: To check these possible causes, proceed

to Testing Ignition System. If no spark is present,
proceed to Arctic Cat Ignition Analyzer in this sec-
tion.

Testing Ignition System

(Single Carburetor F/C Models)

„

NOTE: The throttle control is equipped with a

two-wire throttle control switch connector. There
must be 0.75-1.5 mm (0.030-0.060 in.) throttle cable
free-play between the throttle lever and the control
housing.

MAIN WIRING AND SAFETY 

SWITCHES

1. Check the wiring connections coming from the

ignition key and throttle control switches. The

two-wire throttle control switch connector is

located on the front side of the steering post. If any

of the connections appear dirty or corroded, clean

them with fine sandpaper and compressed air; then

connect all wires and squeeze the connections with

a pliers for additional tightness.

2. Disconnect the main wiring harness four-wire

connector coming from the engine stator

assembly. Disconnecting the connector will

bypass the main wiring harness and all switches

which will not allow the engine to be shut off

without first installing an additional auxiliary

ground wire.

3. Insert an auxiliary ground wire into the black wire

of the four-wire main harness connector on the

engine side. To stop the engine once it has been

started, touch the auxiliary ground wire to the

engine.

4. Support the rear of the snowmobile up on a

shielded safety stand; then set the brake lever lock.

Inspect the complete throttle mechanism to assure

that it's working properly.

5. Attempt to start the engine. To stop the engine (if

the engine starts), touch the auxiliary ground wire

installed into the four-wire connector to a ground

on the engine. If the engine fails to start, the

problem is with the coils mounted on the engine,

high tension coil assembly, or the CDI unit. If the

engine starts, the problem is with the switches,

main wiring harness, or throttle cable free-play.

MAIN HARNESS

1. Disconnect the main wiring harness four-wire

connector coming from the engine stator

assembly. Connect one ohmmeter lead to the

violet wire and the other lead to the brown wire on

the chassis side of the main wiring harness four-

wire connector. With all switches in the RUN

position, the meter must read no resistance (open).

2. If the meter reads resistance (closed), test the

Ignition Key Switch and Throttle Control Switch

independently of each other.

IGNITION KEY SWITCH

1. Disconnect the ignition key switch connectors;

then connect the ohmmeter leads to each of the

ignition key switch terminals.

2. With the key switch in the OFF position, the meter

must read resistance (closed). If the meter reads no

resistance (open), the switch must be replaced.

5-17

5

THROTTLE CONTROL SWITCH

„

NOTE: The throttle control has a two-wire wiring

harness connector located on the front side of the
steering post. Whenever working with a two-wire
throttle control switch, the throttle cable must be
adjusted so there is 0.75-1.5 mm (0.030-0.060 in.)
free-play between the throttle lever and control
housing.

1. Verify that the throttle cable has the specified

amount of free-play between the throttle lever and

control housing.

2. Disconnect the two-wire throttle control switch

connector; then connect the ohmmeter leads to

each of the switch wires.

3. With the throttle lever in the idle position and the

emergency stop knob in the down (STOP)

position, the meter must read resistance (closed).

If the meter reads no resistance (open), replace the

switch.

4. Depress the throttle lever with the emergency stop

knob in the up (RUN) position. The meter must

read no resistance (open). If the meter reads

resistance (closed), replace the switch.

5. With the throttle lever depressed and the

emergency stop knob in the down (STOP)

position, the meter must read resistance (closed).

If the meter reads no resistance (open), replace the

switch.

Testing Ignition System

(Twin Carburetor F/C Models)

„

NOTE: There must be 0.75-1.5 mm (0.030-0.060

in.) free-play between the throttle lever and the
control housing (see Section 4 - Adjusting Carbu-
retors).

MAIN WIRING AND SAFETY 

SWITCHES

1. Check the wire connections at the ignition key

switch and at the emergency stop switch. This

connector is located on the front side of the

steering post. If any of the connections appear

dirty or corroded, clean with fine sandpaper and

compressed air; then connect all wires and squeeze

connections with a pliers for added tightness.

2. Disconnect the main wiring harness connector

coming from the engine. Using an ohmmeter,

connect one lead to the black wire in the connector

of the main harness. Connect the remaining

ohmmeter lead to the brown wire in the connector

of the main harness.

3. With all switches in the RUN position, the meter

must read resistance (closed). If the meter reads no

resistance (open), proceed to testing Emergency

Stop/Throttle Switch, Carburetor Safety Switches,

and Ignition Key Switch.

EMERGENCY STOP/

THROTTLE SWITCH

1. If the meter read no resistance (open) in the

previous test, locate the wiring harness coming

from the emergency stop/throttle switch assembly.

2. Disconnect the three-wire connector. Using an

ohmmeter, connect one meter lead to the black

wire and the other meter lead to the black/red wire

in the connector.

3. With the emergency stop knob, located on top of

the throttle control, in the ON (pulled up) position

and the throttle lever compressed, the meter must

read resistance (closed).

4. If the meter reads no resistance (open) and the

lever/control housing free-play is correct, replace

the throttle switch.

5. If the meter reads resistance (closed) but the

engine will not start, with the ohmmeter leads still

connected, alternately release and compress the

throttle lever; then move the emergency stop knob

down and up.

6. The meter must read no resistance (open) when the

throttle lever is released and the emergency stop

knob is in either the UP or the DOWN position.

7. If the meter reads resistance (closed), replace the

throttle switch.

8. Connect one meter lead to the black/red wire and

the other meter lead to the black/white wire.

9. With the throttle lever released (idle position) and

the emergency stop knob in the DOWN position,

the meter must read no resistance (open).

10. If above tests were good, proceed to testing

Carburetor Safety Switches and Ignition Key

Switch.

CARBURETOR SAFETY SWITCHES

1. If the meter read no resistance (open) in the

previous test, disconnect the carburetor safety

switches one at time and test for a closed circuit.

2. Attach the two ohmmeter leads to the two leads

coming from each carburetor switch. The meter

must read resistance (closed).

3. If the meter reads no resistance (open), the switch

must either be adjusted or replaced (see

Synchronizing Carburetor Safety Switches in this

sub-section). If the meter reads resistance (closed),

proceed to testing Ignition Key Switch.

5-18

IGNITION KEY SWITCH

1. If the meter read resistance (closed) in the

previous test, disconnect the ignition key switch

connectors and connect the ohmmeter leads to

each of the leads from the switch.

2. With the key switch in the OFF position, the meter

must read resistance (closed). If the meter reads no

resistance (open), replace the switch.

SYNCHRONIZING CARBURETOR 

SAFETY SWITCHES

Before synchronizing the carburetor safety switches,

check to make certain the carburetor idle speed screws

are adjusted equally and the piston valves are synchro-

nized. The carburetor safety switches affect ignition

spark at idle only. If ignition spark problems are

observed at partial or full-throttle positions, the prob-

lem is not with the carburetor safety switches.

„

NOTE: There must be 0.75-1.5 mm (0.030-0.060

in.) free-play between the throttle lever and the
control housing.

1. Inspect the cable free-play gap between the

throttle lever and the control housing at idle.

Adjust the throttle cable swivel adapter at the top

of each carburetor for 0.75-1.5 mm (0.030-0.060

in.) cable free-play gap between the throttle lever

“nibs” and the control housing. While observing if

there is any cable free-play gap, apply slight

pressure to the throttle lever to take up any cable

slack that may be present. However, do not apply

enough pressure to actually raise the carburetor

slides during this adjustment. After cable free-play

is properly adjusted, tighten the jam nut on each

carburetor securely.

733-081C

2. To determine which switch needs adjusting,

disconnect both carburetor safety switches from

the main wiring harness connector.

3. Connect a digital ohmmeter to one carburetor

safety switch connector; then compress the throttle

lever while observing the meter reading and

measure the gap between the throttle lever and

control housing at the moment the meter reading

changes from open to closed. Repeat this step for

the other carburetor safety switch.

„

NOTE: The correct throttle lever/housing gap

should be in a range of 9.5 - 12.7 mm (0.375-0.500
in.) the moment the meter reading changes from
open to closed. A switch that changes from open
to closed before the other one is the switch that
must be raised to attain safety switch synchroniza-
tion.

733-082A

4. If an adjustment is necessary, loosen the switch

bracket screws, move the switch up, tighten the

screws, and then reset using step 3.

„

NOTE: After completion of any adjustments,

throttle lever “side pressure” should not cause an
ignition miss at idle. Carburetor switches set too
low or an excessively tight throttle cable makes
the shutdown system very sensitive to throttle
lever “side pressure” near idle. To test carburetor
safety switch synchronization, follow steps 5-9.

5. Reconnect the carburetor safety switch

connectors. Place the rear of the snowmobile on a

shielded safety stand; then start the engine and

allow it to warm up for 3-4 minutes.

6. Hold both the top and bottom of the throttle lever

pin so that depression of the throttle lever does not

move the lever pin in its control slot.

0728-916

7. Slowly depress the throttle lever to increase engine

RPM.

„

NOTE: It is very important that engine RPM be

allowed to increase slowly, since most engines
have a “rich area” at approximately 2500 RPM.