Yamaha YFM4FAR, Service Manual

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ELEC
SIGNAL SYSTEM
4.If the coolant temperature warning light does not come on:
●
Check that the light comes on when the main switch is set to “ON”.
●
Check that the light comes on when the coolant temperature is 120 ± 3 °C (248 ± 5.4 °F) or higher
and that the light remains on when the coolant temperature drops to 113 °C (235.4 °F).
CONTINUITY
1.Bulb and bulb socket
Check the bulb and bulb socket for
continuity.
NO CONTINUITY
Replace the bulb and/or bulb socket.
C0NTINUITY
2.Thermo switch (cylinder head)
●
Remove the thermo switch (cylinder head)
from the cylinder head.
●
Connect the pocket tester (
Ω ×
1) to the
thermo switch (cylinder head)
1
.
●
Immerse the thermo switch (cylinder head)
in coolant
2
.
●
Check the thermo switch (cylinder head) for
continuity.
While heating the coolant use a thermometer
3
to record the temperatures.
Test
step
Coolant temperature
Continuity
Thermo switch
(cylinder head)
1
Less than 120 ± 3 °C
(248 ± 5.4 °F)
NO
2
More than 120 ± 3 °C
(248 ± 5.4 °F)
YES
3
More than 113 °C
(235.4 °F)
YES
4
Less than 113 °C
(235.4 °F)
NO
Test steps 1 & 2: Heating phase
Test steps 3 & 4: Cooling phase
È
The thermo switch (cylinder head) circuit is
open and the coolant temperature warning
light is off.
É
The thermo switch (cylinder head) circuit is
closed and the coolant temperature warning
light is on.
*
É
È
113 ˚C
(235.4 ˚F)
120 ± 3 ˚C
(248 ± 5.4 ˚F)