ignition YAMAHA TTR90 2002 User Guide

6 - 4
–+ELECIGNITION SYSTEM
EC626002
IGNITION COIL INSPECTION
1. Inspect:
lPrimary coil resistance
Out of specification ® Replace.
Tester (+) lead ® Orange lead 1
Tester (–) lead ® Black lead 2
Primary coil
resistanceTester selector
position
0.18 ~ 0.28 W at
20 ˚C (68 ˚F)W ´ 1
2. Inspect:
lSecondary coil resistance
Out of specification ® Replace.
NOTE:
When inspecting the secondary coil resis-
tance, remove the spark plug cap.
CDI MAGNETO INSPECTION
1. Inspect:
lPickup coil resistance
Out of specification ® Replace. Tester (+) lead ® Spark plug lead 1
Tester (–) lead ® Orange lead 2
Secondary coil
resistanceTester selector
position
6.3 ~ 9.5 kW at
20 ˚C (68 ˚F)kW ´ 1
Tester (+) lead ® Red lead 1
Tester (–) lead ® White lead 2
Pickup coil
resistanceTester selector
position
248 ~ 372 W at
20 ˚C (68 ˚F)W ´ 100

6 - 5
–+ELECIGNITION SYSTEM
2. Inspect:
lSource coil resistance
Out of specification ® Replace.
Tester (+) lead ® Brown lead 1
Tester (–) lead ® Green lead 2
Source coil
resistanceTester selector
position
688 ~ 1,032 W
at 20 ˚C (68 ˚F)W ´ 100

6 - 7
–+ELECCARBURETOR HEATING SYSTEM
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
lCouplers and leads connection
Rust/dust/looseness/short-circuit ®
Repair or replace.
CDI MAGNETO INSPECTION
1. Inspect:
lSource coil resistance
Refer to “IGNITION SYSTEM” section.
THERMO SWITCH INSPECTION
1. Inspect:
lThermo switch operation
Faulty operation ® Replace.
Inspection steps:
lRemove the thermo switch.
lConnect the pocket tester to the thermo
switch coupler as shown.
Tester (+) lead ® Black 1
Tester (–) lead ® Black 2
lImmerse the thermo switch in a container
filled with water 3.
lPlace a thermometer 4 in the water.
lSlowly heat the water, and then let it cool to
the specified temperature as indicated in
the table.
lCheck the thermo switch for continuity at
the temperatures indicated in the table.