Ignition System (For Hatchback) -- On-Vehicle Inspection |
1. PERFORM SPARK TEST |
Check for DTCs (YARIS_NCP93 RM000000PDK0T5X.html).
- NOTICE:
- If any DTC is present, perform troubleshooting in accordance with the procedure for that DTC.
Remove the 4 ignition coils and 4 spark plugs (YARIS_NCP93 RM000002YO404IX.html).
Disconnect the 4 injector connectors.
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Install a spark plug to each ignition coil and connect the ignition coil connectors.
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Ground the spark plugs.
Check that spark occurs while the engine is being cranked.
Check whether sparks occur.
- NOTICE:
- Ground the spark plugs when checking them.
- Replace any ignition coils that have been subjected to a physical impact.
- Do not crank the engine for more than 2 seconds.
If spark does not occur, perform the following procedure.
2. INSPECT IGNITION COIL AND SPARK TEST |
Perform the spark test in accordance with the following procedure.
Check that the wire harness side connector of the ignition coil with igniter is securely connected.
Result: Result Proceed to NG Connect securely OK Go to next step
Perform a spark test on each ignition coil with igniter.
If there is a cylinder where sparks do not occur, replace its ignition coil with the ignition coil of a cylinder where sparks occur normally.
Crank the engine and visually check that sparks occur at the cylinder with the normally operating ignition coil.
Result: Result Proceed to NG Replace ignition coil with igniter OK Go to next step
Perform a spark test on each spark plug.
If there is a cylinder where sparks do not occur, replace its spark plug with the spark plug of a cylinder where sparks occur normally.
Crank the engine and visually check that sparks occur at the cylinder with the normally operating spark plug.
Result: Result Proceed to NG Replace spark plug OK Ignition Circuit
Connect the 4 injector connectors.
Install the ignition coil and spark plug (YARIS_NCP93 RM000002YO204IX.html).
3. INSPECT SPARK PLUG |
- NOTICE:
- Do not use a wire brush for cleaning.
- Do not attempt to adjust the electrode gap of a used spark plug.
Check the electrode.
Text in Illustration *1 Body Ground Measure the insulation resistance.
- Standard Resistance:
- 10 MΩ or more
- HINT:
- If the result is not as specified, clean the spark plug with a spark plug cleaner and measure the resistance again.
- If a megohmmeter is not available, perform the following simple inspection instead.
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Alternative inspection method:
Quickly accelerate the engine to 4000 rpm 5 times.
- NOTICE:
- When DTC P0300 (Random / Multiple Cylinder Misfire Detected) or related DTCs are output, do not perform this step.
Remove the spark plug.
Visually check the spark plug.
If the electrode is dry, the spark plug is functioning properly. If the electrode is damp, proceed to the next step.
Check the spark plug for any damage to its thread and insulator.
If there is any damage, replace the spark plug.- Recommended Spark Plug:
Manufacturer Product DENSO FK16HR11
Clean the spark plug.
If the electrode has traces of wet carbon, clean the electrode with a spark plug cleaner and then dry with compressed air.- Air Pressure:
- 588 kPa (6 kgf/cm2, 85 psi)
- Duration:
- 20 seconds or less
- HINT:
- Only use the spark plug cleaner when the electrode is free of oil. If the electrode has traces of oil, use gasoline to clean off the oil before using the spark plug cleaner.