Snowmobile Yamaha Phazer PZ50 (2007-2008 year). Manual - part 69

7-22

FI

FUEL INJECTION SYSTEM

Fault code No.

42

Symptom

No normal signals are received from the speed sensor.

Diagnostic code No. 07 (speed sensor)

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Connections

Speed 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.

Starting the 
engine, and 
inputting the 
vehicle speed 
signals by oper-
ating the snow-
mobile at a low 
speed of 20 to 
30 km/h.

2

Open or short circuit in wire harness.

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

Blue – Blue
White/Yellow – White/Yellow
Black/Blue – Black/Blue

3

Defective speed sensor.

Execute the diagnostic mode (code No. 07). 
Replace if defective.
Refer to “SIGNAL SYSTEM” in CHAPTER 8.

4

Gear for detecting vehicle speed has 
broken.

Replace if defective.
Refer to “FRONT AXLE AND TRACK” in CHAP-
TER 4.

7-23

FI

FUEL INJECTION SYSTEM

Fault code No.

43

Symptom

ECU is unable to monitor the battery voltage (an open or short circuit in the 
line to the ECU).

Diagnostic code No. 09 (fuel system voltage)

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Connections

Fuel injection system relay 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.

Starting the 
engine and 
operating it at 
idle.

2

Open or short circuit in wire harness.

Repair or replace if there is an open or short cir-
cuit.
Between fuel injection system relay coupler and 
ECU coupler.

Blue/Red – Blue/Red

Between fuel injection system relay coupler and 
engine stop switch coupler.

Red/White – Red/White

Between engine stop switch coupler and main 
switch coupler.

Brown – Brown

3

Malfunction or open circuit in fuel injec-
tion system relay.

Execute the diagnostic mode (code No. 09). 
Replace if defective.

NOTE:

When the leads are disconnected, the voltage 
check by the code No. 09 is impossible.

1. Disconnect the fuel injection system relay from 

the wire harness and remove it.

2. Connect the pocket tester (

Ω × 1) and battery 

(12 V) to the fuel injection system relay termi-
nals as shown.

3. Does the fuel injection system relay have con-

tinuity between the red/green and red/blue ter-
minals?

Positive battery terminal 

→ Red/White 1 

Negative battery terminal 

→ Blue/Red 2 

Positive tester probe 

→ Red/Green 3 

Negative tester probe 

→ Red/Blue 4 

7-24

FI

FUEL INJECTION SYSTEM

Fault code No.

44

Symptom

Error is detected while reading or writing on EEPROM (CO adjustment 
value).

Diagnostic No. 60 (EEPROM improper cylinder indication)

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Malfunction in ECU.

Execute the diagnostic mode (code No. 60).
1. Check the faulty cylinder. (If both cylinders are 

defective, the display alternates every 2 sec-
onds.)

2. Readjust the CO of the displayed cylinder.
Replace ECU if defective.

Turning the 
main switch on.

Fault code No.

46

Symptom

Power supply to the fuel injection system is not normal.

Diagnostic code No. – –

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Connections

Wire harness ECU coupler

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

Starting the 
engine and 
operating it at 
idle.

2

Faulty battery.

Replace or charge the battery.
Refer to “BATTERY INSPECTION” in CHAPTER 
2.

3

Malfunction in rectifier/regulator.

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

4

Open or short circuit in wire harness.

Repair or replace if there is an open or short cir-
cuit.
• Between battery and ignition fuse.

Red – Red

• Between ignition fuse and main switch coupler.

Red/Yellow – Red/Yellow

• Between main switch coupler and load control 

relay coupler.

Brown – Brown

• Between load control relay coupler and ECU 

coupler.

Brown/Blue – Brown/Blue

Fault code No.

50

Symptom

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

Diagnostic code No. – –

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Malfunction in ECU.

Replace the ECU.

Turning the 
main switch on.

7-25

FI

FUEL INJECTION SYSTEM

Fault code No.

65

Symptom

Knock sensor: open or short circuit detected.

Diagnostic code No. – –

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Installed condition of knock sensor

Check for looseness or pinching.

Starting the 
engine and 
operating it at 
idle.

2

Connections

Knock 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.

3

Open or short circuit in wire harness.

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

White – White

4

Defective knock sensor.

Replace if defective.
Refer to “KNOCK SENSOR” in CHAPTER 8.

Fault code No.

81

Symptom

Grip warmer: open or short circuit detected.

Diagnostic code No. 26 (grip warmer operation)

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Open or short circuit in wire harness.

Repair or replace if there is an open or short cir-
cuit.
Between grip warmer coupler and ECU coupler.

Yellow/Red – Yellow/Red

Turning the 
main switch on.

Fault code No.

83

Symptom

Thumb warmer: short circuit detected.

Diagnostic code No. 27 (thumb warmer operation)

Order

Item/components and probable cause

Check or maintenance job

Reinstatement 
method

1

Short circuit in wire harness.

Repair or replace if there is a short circuit. 
Between thumb warmer coupler and ECU cou-
pler.

Light green – Light green

Turning the 
main switch on.