Yamaha Waverunner VXS VX1800 Service Manual page 307

Symptom 2
Discharged battery
ECM does not oper-
ate
Spark plug does not
spark (all cylinders)
Cause
Battery performance de-
crease
Stator coil malfunction
Short, open, or loose con-
nection in charging circuit
Blown fuse
Main relay malfunction
Short, open, or loose con-
nection in ECM circuit
ECM malfunction
Engine shut-off cord clip
not installed
Engine stop switch mal-
function
Pickup coil malfunction
Short, open, or loose con-
nection in pickup coil circuit
Short, open, or loose con-
nection in ignition coil cir-
cuit
Ignition coil malfunction
ECM malfunction
Checking step
Check the battery voltage and spe-
cific gravity.
Check the stator coil
Check the battery lead and terminal
for proper connection.
Check the wire harness.
Check the fuse for continuity.
Check the main relay.
Measure the ECM input voltage.
Check the ECM circuit for continuity.
Replace the ECM.
Check that the engine shut-off cord
clip is installed properly.
Check the engine stop switch conti-
nuity. [handlebar switch (left)]
Measure the pickup coil output peak
voltage.
Measure the pickup coil resistance.
Check the white/black (W/B) and
black/orange (B/O) pickup coil leads
for continuity.
Measure the ignition coil input volt-
age (from the battery).
Check the red/yellow (R/Y),
black/red (B/R), black/white (B/W),
black/yellow (B/Y), and black/green
(B/G) ignition coil leads for continui-
ty.
Exchange the ignition coil with a dif-
ferent one, and then check the igni-
tion spark.
Measure the ECM output peak volt-
age.
9-16
Engine unit troubleshooting
See
page
3-6
7-13
3-6
A-2
7-3
7-31
7-31
7-27
7-27
—
7-31
7-31
7-12
7-12
A-2
7-11
A-2
—
7-11