Yamaha F150B, Service Manual

Page: 159 / 458

5-34
Ignition units and components
0
1
2
3
4
5
6
7
8
9
10
A
3. Turn the engine start switch to “OFF.”
4. Remove the engine temperature sensor.
5. Place the engine temperature sensor in a
container of water and slowly heat the
water.
6. Measure the engine temperature sensor
resistance. Replace if out of specifica-
tion.
7. Install the engine temperature sensor.
8. Remove the junction box cover, and then
disconnect the engine ECM coupler
b
.
9. Check the wiring harness for continuity.
10. Connect the engine ECM coupler
b
, and
then install the junction box cover.
11. Connect the engine temperature sensor
coupler
a
.
Checking the thermoswitch
1. Disconnect the thermoswitch connectors.
Engine temperature sensor input voltage:
Black/Yellow (B/Y)–Black (B)
4.75–5.25 V
Engine temperature sensor resistance
(reference data):
54.2–69.0 k
Ω
at 20 °C (68 °F)
3.12–3.48 k
Ω
at 98 °C (208 °F)
a
B B/Y
Wiring harness continuity:
Terminal 1–Terminal 35
Terminal 2–Terminal 8
b
8
a
b
35