Yamaha F150B - Checking the Engine ECM Circuit

5-15
ELEC
Electrical system
4. Turn the engine start switch to “ON,” and
then measure the input voltage between
terminals f and g.
5. Turn the engine start switch to “OFF,” and
then install the main relay a.
Checking the engine ECM circuit
1. Remove the junction box cover, and then
disconnect the engine ECM coupler a.
2. Check for continuity between the engine
ECM coupler terminals (32 and 42) and
ground.
3. Measure the input voltage at the engine
ECM coupler terminal 16 and ground.
4. Turn the engine start switch to “ON,” and
then measure the input voltage at the
engine ECM coupler terminal 13 and
ground.
Main relay input voltage:
Ter m ina l f–Terminal g
12.0 V (battery voltage)
g
f
a
Engine ECM input voltage:
Terminal 16–Ground
12.0 V (battery voltage)
42
32
a
a
16