Suzuki SFV650, Service Manual

Page: 330 / 573

1H-3 Ignition System:
No Spark or Poor Spark
B944H11804002
Troubleshooting
NOTE
Check that the transmission is in neutral and the engine stop switch is in the “RUN” position. Grasp
the clutch lever. Check that the fuse is not blown and the battery is fully-charged before diagnosing.
Step Action Yes No
1 Check the ignition system couplers for poor connections.
Is there connection in the ignition system couplers?
Go to Step 2. Poor connection of
couplers.
2 Measure the battery voltage between input lead wires (E-02,
19, 24: O/G and B/W, E-03, 28, 33: O/W and B/W) at the
ECM with the ignition switch in the “ON” position.
Is the voltage OK?
Go to Step 3. • Faulty ignition switch.
• Faulty turn signal /
side-stand relay.
• Faulty engine stop
switch.
• Broken wire harness
or poor connection of
related circuit
couplers.
3 Measure the ignition coil primary peak voltage. Refer to
“Ignition Coil and Plug Cap Inspection (Page 1H-6)”.
NOTE
This inspection method is applicable only with
the multi-circuit tester and the peak volt adaptor.
Is the peak voltage OK?
Go to Step 4. Go to Step 5.
4 Inspect the spark plugs. Refer to “Spark Plug Inspection and
Cleaning in Section 0B (Page 0B-9)”.
Is the spark plug OK?
Go to Step 5. Faulty spark plugs.
5 Inspect the ignition coils. Refer to “Ignition Coil and Plug Cap
Inspection (Page 1H-6)”.
Is the ignition coil OK?
Go to Step 6. Faulty ignition coil.
6 Measure the CKP sensor peak voltage and its resistance.
Refer to “CKP Sensor Inspection (Page 1H-8)”.
NOTE
The CKP sensor peak voltage inspection is
applicable only with the multi-circuit tester and
peak volt adaptor.
Are the peak voltage and resistance OK?
• Faulty ECM.
• Open or short circuit
in wire harness.
• Poor connection of
ignition wire harness.
• Faulty CKP sensor.
• Metal particles or
foreign material being
stuck on the CKP
sensor and rotor tip.