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Ignition Coil: Testing and Inspection

Component Inspection

IGNITION COIL WITH POWER TRANSISTOR

CAUTION: Do the following procedure in the place where ventilation is good without the combustible.

1. Turn ignition switch OFF.
2. Disconnect ignition coil harness connector.




3. Check resistance between ignition coil terminals as shown.
4. If NG, replace ignition coil with power transistor.
If OK, go to next step.

5. Turn ignition switch OFF.
6. Reconnect all harness connectors disconnected.




7. Remove fuel pump fuse in fuse block No. 1 to release fuel pressure.

NOTE: Do not use CONSULT-II to release fuel pressure, or fuel pressure applies again during the following procedure.

8. Start engine.
9. After engine stalls, crank it two or three times to release all fuel pressure.
10. Turn ignition switch OFF.
11. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.
12. Remove ignition coil and spark plug of the cylinder to be checked.
13. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
14. Connect spark plug and harness connector to ignition coil.




15. Fix ignition coil using a rope etc. with gap of 13 - 17 mm between the edge of the spark plug and grounded metal portion as shown in the figure.
16. Crank engine for about 3 seconds, and check whether spark is generated between the spark plug and the grounded metal portion.

Spark should be generated.

CAUTION:
- Do not approach to the spark plug and the ignition coil within 50 cm. Be careful not to get an electrical shock while checking, because the electrical discharge voltage becomes 20 kV or more.
- It might cause to damage the ignition coil if the gap of more than 17 mm is taken.

NOTE: When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.

17. If NG, replace ignition coil with power transistor.