Snowmobile Yamaha FX10X, FX10RTX, FX10RTRX, FX10RTRAX, FX10MTX, FX10MTRX, FX10MTRAX. Manual - part 70

7-10

Engine speed is high when
the engine is idling.

• Open or short circuit in wire harness.
• Open or short circuit in fuel injection system sub-wire harness.
• Malfunction in throttle body.
• Malfunction in throttle cable.
• ISC valve is stuck fully open due to disconnected ISC unit hose

or coupler. (High engine idle speed is detected with the ISC
valve stuck fully open even though signals for the valve to close
are continuously being transmitted by the ECU.)

• Malfunction in ECU.

No normal signals are
received from the speed sen-
sor.

• Open or short circuit in wire harness.
• Defective speed sensor.
• Malfunction in ECU.

Power supply to the fuel
injectors and fuel pump is not
normal.

• Open or short circuit in wire harness.
• Malfunction in ECU.

Error is detected while read-
ing or writing on EEPROM
(CO adjustment value).

• Malfunction in ECU. (The CO adjustment value is not properly

written on or read from the internal memory.)

Power supply to the fuel
injection system is not nor-
mal.

• Malfunction in the charging system. (Refer to “CHARGING SYSTEM” in

CHAPTER 8.)

—

Faulty ECU memory. (When
this malfunction is detected in
the ECU, the fault code num-
ber might not appear on the
meter.)

• Malfunction in ECU. (The program and data are not properly

written on or read from the internal memory.)

—

Grip warmer: open or short
circuit detected.

• Open or short circuit in wire harness.
• Defective grip warmer.
• Malfunction in ECU.

Thumb warmer: short circuit
detected.

• Short circuit in wire harness.
• Defective thumb warmer.
• Malfunction in ECU.

Conditions requiring T.O.R.S.
operation are detected.

• Open or short circuit in wire harness.
• Open or short circuit in fuel injection system sub-wire harness.
• Defective throttle position sensor.
• Defective throttle switch.
• Defective speed sensor.
• Malfunction in ECU.
• Improperly installed throttle position sensor.

01
07
24

Oil pressure switch: open cir-
cuit detected.

• Open circuit in wire harness.
• Open circuit in oil pressure switch sub-lead.
• Defective oil pressure switch.
• Malfunction in ECU.

—

Er-1

No signals are received from
the ECU.

• Open or short circuit in wire harness.
• Malfunction in speedometer unit.
• Malfunction in ECU.
• Defective wire connection of the ECU coupler.

—

Er-2

No signals are received from
the ECU within the specified
signal time.

• Improper connection in wire harness.
• Malfunction in speedometer unit.
• Malfunction in ECU.

—

Er-3

Data from the ECU cannot be
received correctly.

• Improper connection in wire harness.
• Malfunction in speedometer unit.
• Malfunction in ECU.

—

Er-4

Non-registered data has been
received from the meter.

• Improper connection in wire harness.
• Malfunction in speedometer unit.
• Malfunction in ECU.

—

Fault

code No.

Symptom

Probable cause of malfunction

Diagnostic code No.

7-11

FUEL INJECTION SYSTEM

Diagnostic mode table
Switch the meter display from the regular mode to the diagnostic mode. To switch the display, refer to “DIAG-
NOSTIC MODE”.

NOTE:

• Check the intake air temperature and coolant temperature as close as possible to the intake air temperature

sensor and the coolant temperature sensor respectively.

• If it is not possible to check the intake air temperature, use the ambient temperature as reference.

Diagnostic

code No.

Item

Description of action

Data displayed on meter

(reference value)

Throttle angle

Displays the throttle angle.
• Check with throttle fully closed.
• Check with throttle fully open.

0 ~ 125 degrees
• Fully closed position (15 ~ 18)
• Fully open position (94 ~ 100)

Intake air pressure sensor
1 (atmospheric pressure
and intake air pressure)

Displays the intake air pressure for cylinders #1, #2, and
#3.

• Not cranking: atmospheric

pressure

• Cranking: intake air pressure

decreases to less than the
atmospheric pressure.

Intake air pressure sensor
2 (atmospheric pressure
and intake air pressure)

Displays the intake air pressure for cylinder #1.

• Not cranking: atmospheric

pressure

• Cranking: intake air pressure

decreases to less than the
atmospheric pressure.

Intake air temperature

Displays the intake air temperature.
• Check the temperature in the air filter case.

Compare it to the value dis-
played on the meter. (Minimum
displayed value: –30 [°C])

Coolant temperature

Displays the coolant temperature.
• Check the temperature of the coolant.

Compare it to the value dis-
played on the meter. (Minimum
displayed value: –30 [°C])

Snowmobile speed pulse

Displays the cumulative number of snowmobile pulses
that are generated when the track is spun.

(0 ~ 999; resets to 0 after 999)
OK if the numbers appear on
the meter.

Fuel system voltage (bat-
tery voltage)

Displays the fuel system voltage (battery voltage).

0 ~ 18.7 V
Normally, approximately 12.0 V

Throttle switch

Displays that the switch is on or off.

Throttle open: on
Throttle closed: off

Grip warmer operation

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the grip warmer and
displays the self-diagnosis warning indicator for 120 sec-
onds.

—

Thumb warmer operation

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the thumb warmer and
displays the self-diagnosis warning indicator for 120 sec-
onds.

—

Cylinder-#1 ignition coil

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the cylinder-#1 ignition
coil and displays the self-diagnosis warning indicator
(five times at one-second intervals).

After pushing the switch, check
that a spark is produced five
times.

Cylinder-#2 ignition coil

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the cylinder-#2 ignition
coil and displays the self-diagnosis warning indicator
(five times at one-second intervals).

After pushing the switch, check
that a spark is produced five
times.

Cylinder-#3 ignition coil

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the cylinder-#3 ignition
coil and displays the self-diagnosis warning indicator
(five times at one-second intervals).

After pushing the switch, check
that a spark is produced five
times.

Injector #1

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates injector #1 and displays
the self-diagnosis warning indicator (five times at one-
second intervals).

After pushing the switch, check
that the injector operates five
times by listening to its operat-
ing sound.

7-12

FUEL INJECTION SYSTEM

Injector #2

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates injector #2 and displays
the self-diagnosis warning indicator (five times at one-
second intervals).

After pushing the switch, check
that the injector operates five
times by listening to its operat-
ing sound.

Injector #3

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates injector #3 and displays
the self-diagnosis warning indicator (five times at one-
second intervals).

After pushing the switch, check
that the injector operates five
times by listening to its operat-
ing sound.

Fuel injection system relay

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the fuel injection sys-
tem relay and displays the self-diagnosis warning
indicator (five times at one-second intervals). (The indi-
cator is off when the relay is on and it is on when the
relay is off.)

After pushing the switch, check
that the fuel injection system
relay operates five times by lis-
tening to its operating sound.

Radiator fan motor relay

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the radiator fan motor
relay (on/off) and displays the self-diagnosis warning
indicator (for five cycles of five seconds each). (The
relay and indicator are on for two seconds and off for
three seconds.)

After pushing the switch, check
that the radiator fan motor relay
operates five times by listening
to its operating sound. (At that
time, the fan motor rotates.)

Headlight relay

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the headlight relay (on/
off) and displays the self-diagnosis warning indicator (for
five cycles of five seconds each). (The relay and indica-
tor are on for two seconds and off for three seconds.)

After pushing the switch, check
that the headlight relay oper-
ates five times by listening to
its operating sound. (At that
time, the headlight and taillight
come on.)

ISC (idle speed control)
unit

If the grip warmer side of the grip/thumb warmer adjust-
ment switch is pushed, actuates the ISC (idle speed
control) valve (fully closes/opens) for three cycles of four
seconds each and displays the self-diagnosis warning
indicator. (The valve fully closes in two seconds and
opens in two seconds.)

After pushing the switch, check
that the ISC unit vibrates. The
ISC vibrates when the ISC
valve operates.

EEPROM fault code dis-
play

• Displays the cylinder number if an error is detected in

the EEPROM CO adjustment value for the cylinder as
fault code No. 44.

• If multiple cylinders are defective, the display alter-

nates every 2 seconds.

(01 ~ 03) Displays the cylinder
number.
(00) Displays when there is no
malfunction.

Malfunction history code
display

• Displays the code numbers of past malfunctions (i.e., a

code number of a malfunction that occurred once and
which has been corrected).

• If more than one code number is detected, the display

alternates every 2 seconds to show all the detected
code numbers. When all code numbers are shown, the
display repeats the same process.

12 ~ 85
(00) Displays when there is no
malfunction.

Malfunction history code
erasure

• Displays the total number of codes that are being

detected through self diagnosis and the fault codes in
the past history.

• Erases only the history codes when the grip warmer

side of the grip/thumb warmer adjustment switch is
pushed.

00 ~ 23
(00) Displays when there is no
malfunction.

Control number

• Displays the program control number.

00 ~ 255

Diagnostic

code No.

Item

Description of action

Data displayed on meter

(reference value)

7-13

FUEL INJECTION SYSTEM

TROUBLESHOOTING DETAILS

This section describes the measures per fault code number displayed on the meter. Check and service the
items or components that are the probable cause of the malfunction following the order given.
After the check and service of the malfunctioning part have been completed, reset the meter display accord-
ing to the reinstatement method.
Fault code No.:

Code number displayed on the meter when the engine failed to work normally. (Refer to “Fault code
table”.)

Diagnostic code No.:

Code number to be used when the diagnostic mode is operated. (Refer to “Diagnostic mode table”.)

Fault code No.

Symptom

No normal signals are received from the crankshaft position sensor.

Diagnostic code No. – –

Order

Item/components and probable cause

Check or maintenance job

Reinstatement
method

Installed condition of crankshaft position
sensor.

Check for looseness or pinching.

Cranking the
engine.

Connections

Crankshaft position sensor coupler
Wire harness ECU coupler

Check the couplers for any pins that may have
pulled out.
Check the locking condition of the couplers.
If there is a malfunction, repair it and connect the
coupler securely.

Open or short circuit in wire harness.

Repair or replace if there is an open or short cir-
cuit.
Between the crankshaft position sensor coupler
and ECU coupler.

Gray – Gray
Black/Blue – Black/Blue

Defective crankshaft position sensor.

Replace if defective.
Refer to “IGNITION SYSTEM” in CHAPTER 8.

Content .. 68 69 70 71 ..