Suzuki LT-A400 Service Manual

1H-2 Ignition System:
No Spark or Poor Spark
B827H11804002
Troubleshooting
NOTE
Check that the transfer is in neutral and the engine stop switch is in the “RUN” position. Check that the
fuse is not blown and the battery is fully-charged before diagnosing.
Spark plug quickly
becomes fouled with oil
or carbon
Worn piston ring. Replace.
Worn piston. Replace.
Worn cylinder. Rebore or replace.
Excessive valve-stem to valve-stem to
valve-guide clearance.
Replace.
Worn valve stem oil seals. Replace.
Spark plug electrodes
overheat or burn
Incorrect spark plug (Hot type). Change to cold type spark plug.
Overheated engine. Tune-up.
Loose spark plug. Tighten.
Excessively lean air/fuel mixture. Adjust carburetor.
Condition Possible cause Correction / Reference Item
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 (O/W
and B/W) at the CDI unit with the ignition switch in ON
position.
Is the voltage OK?
Go to Step 3. • Faulty ignition switch.
• Faulty wire harness.
• 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-3)”.
NOTE
This inspection method is applicable only with
the multi-circuit tester and peak voltage adaptor.
Is the peak voltage OK?
Go to step 4. Go to step 5.
4 Inspect the spark plug. Refer to “Spark Plug Inspection and
Cleaning in Section 0B (Page 0B-6)”.
Is the spark plug OK?
Go to Step 5. Faulty spark plug.
5 Inspect the ignition coil. Refer to “Ignition Coil and Plug Cap
Inspection (Page 1H-3)”.
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-5)”.
NOTE
The CKP sensor peak voltage inspection is
applicable only with the multi-circuit tester and
peak voltage adaptor.
Are the peak voltage and resistance OK?
• Faulty CDI unit.
• 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.

Suzuki LT-A400 Specifications

General

Brand	Suzuki
Model	LT-A400
Category	Offroad Vehicle
Language	English