Snowmobile Yamaha Phazer PZ50W, PZ50GTW, PZ50FXW, PZ50MW, PZ50VTW, PZ50MPW. Manual - part 78

8-24

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+

ELEC

LIGHTING SYSTEM

TROUBLESHOOTING

Check the headlight bulb(s).

Check the main fuse, ignition fuse, and headlight 
fuse.
Refer to “FUSE INSPECTION” in CHAPTER 2.

Check the battery.
Refer to “BATTERY INSPECTION” in CHAPTER 2.

Check the stator coil.
Refer to “CHARGING SYSTEM”.

Check the engine stop switch and main switch.
Refer to “IGNITION SYSTEM”.

Check the headlight beam switch.

Check the headlight relay.

Check the load control relay.

Check the lighting system’s wiring.
Refer to “CIRCUIT DIAGRAM”.

Correct the connection and/or replace the 
speedometer unit, rectifier/regulator, and/or ECU.

HEADLIGHT AND/OR HIGH BEAM INDICATOR LIGHT AND/OR METER LIGHT DO NOT COME ON.

OK

NO CONTINUITY

Replace the bulb(s).

OK

FAULTY

Replace the main fuse, ignition fuse, and/or head-
light fuse.

OK

OUT OF SPECIFICATION

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

OK

OUT OF SPECIFICATION

Replace the stator coil assembly.

OK

FAULTY

Replace the right handlebar switch and/or main 
switch.

OK

FAULTY

Replace the left handlebar switch.

OK

FAULTY

Replace the headlight relay.

OK

FAULTY

Replace the load control relay.

OK

FAULTY

Properly connect or repair the lighting system’s 
wiring.

8-25

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+

ELEC

LIGHTING SYSTEM

Check the main fuse, ignition fuse, and signal fuse.
Refer to “FUSE INSPECTION” in CHAPTER 2.

Check the battery.
Refer to “BATTERY INSPECTION” in CHAPTER 2.

Check the stator coil.
Refer to “CHARGING SYSTEM”.

Check the engine stop switch and main switch.
Refer to “IGNITION SYSTEM”.

Check the load control relay.

Check the lighting system’s wiring.
Refer to “CIRCUIT DIAGRAM”.

Correct the connection and/or replace the tail/brake 
light, rectifier/regulator, and/or ECU.

TAIL LIGHT DOES NOT COME ON.

OK

FAULTY

Replace the main fuse, ignition fuse, and/or signal 
fuse.

OK

OUT OF SPECIFICATION

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

OK

OUT OF SPECIFICATION

Replace the stator coil assembly.

OK

FAULTY

Replace the right handlebar switch and/or main 
switch.

OK

FAULTY

Replace the load control relay.

OK

FAULTY

Properly connect or repair the lighting system’s 
wiring.

8-26

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+

ELEC

LIGHTING SYSTEM

BULB(S)

NOTE:

Do not check any of the lights that use LEDs.

1. Remove:

• Headlight bulb 

2. Connect:

• Pocket tester

(to the bulb terminals)

WARNING

Keep flammable products and your hands away
from the bulb while it is on; it will be hot. Do not
touch the bulb until it cools down.

3. Check:

• Bulb(s)

Terminal

Continuity

1 – 3 Yes

2 – 3 Yes

HEADLIGHT BEAM SWITCH

1. Disconnect:

• Headlight beam switch coupler 

2. Connect:

• Pocket tester

(to the headlight beam switch coupler)

3. Check:

• Headlight beam switch continuity

Faulty 

→ Replace the left handlebar switch.

Switch position

Continuity 

HI

Yes

LO

No

L

G

+

–

Ω × 1

8-27

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+

ELEC

LIGHTING SYSTEM

HEADLIGHT RELAY

1. Remove:

• Headlight relay (with the black coupler) 

Inspection steps:

• Connect the pocket tester (

Ω × 1) to the head-

light relay terminals as shown.

• If headlight relay does not have continuity

between the blue/white and green terminals,
replace it.

• Connect the pocket tester (

Ω  × 1) and battery

(12 V) to the headlight relay terminals as shown.

• If headlight relay does not have continuity

between the blue/white and yellow terminals,
replace it.

Positive tester probe 

→ Blue/White 1 

Negative tester probe 

→ Green 2 

Positive battery terminal 

→ Light green 3 

Negative battery terminal 

→ Black 4 

Positive tester probe 

→ Blue/White 5 

Negative tester probe 

→ Yellow 6 

1

2

L/W

Y

Lg

B

G

6

5

4

3

L/W

Y

Lg

B

G

LOAD CONTROL RELAY

1. Remove:

• Load control relay 

Inspection steps:

• Connect the pocket tester (

Ω  × 1) and battery

(12 V) to the load control relay terminals as
shown.

• If load control relay does not have continuity

between the red and white terminals, replace it.

Positive battery terminal 

→ Brown 1 

Negative battery terminal 

→ Brown/Blue 2 

Positive tester probe 

→ Red 3 

Negative tester probe 

→ White 4 

4

3

2

1

R

W

Br

Br/L