The J20B engine uses an electronic ignition system that has neither distributor nor high-tension cords. It consists of the following
- ECM ECM monitors engine and vehicle conditions through the signals from the relevant sensors, determines the most suitable ignition timing and sends correct signals to ignition coil assemblies.
- Ignition coil assemblies The ignition coil assembly is a combination of an ignitor and ignition coils. It is provided for each cylinder and the ignition coils fit directly over each spark plug. The current to the primary coil is turned on and off according to the signal from the ECM. When the current flowing through the primary coil is broken, a high voltage is induced in the secondary coil. The high voltage is applied directly to the spark plug of each cylinder.
- Spark plugs
- CMP (camshaft position) sensor and CKP (crankshaft position) sensor Using signals from these sensors, ECM identifies a specific cylinder whose piston is in the compression stroke, defects the crank angle and adjusts the initial ignition timing automatically.
- TP (throttle position) sensor, ECT (engine coolant temperature) sensor, MAF (mass air flow) sensor, IAT (intake air temperature) sensor, knock sensor and other sensors/switches ECM controls the ignition timing also using signals from these sensors/switches in addition to signals from the CMP and CKP sensors.
Scheme 1
Scheme 2
| Step | Action | YES | NO |
|---|---|---|---|
| 1 | Was "Engine and Emission Control System Check" performed? | Go to Step 2. | Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK . |
| 2 | Ignition spark test 1 Perform IGNITION SPARK TEST . Is test result satisfactory? | Go to Step 3. | Go to Step 4. |
| 3 | Ignition timing check Check ignition timing. See IGNITION TIMING INSPECTION . Is check result satisfactory? | Ignition system is in good condition. | Repair or replace malfunctioning part. |
| 4 | Confirmation of malfunction-detected cylinder Confirm any cylinder that the malfunction is detected on ignition spark test. Are there malfunctions in all cylinders? | Go to Step 8. | Go to Step 5. |
| 5 | Ignition spark test 2 Replace spark plug in malfunction-detected cylinder with spark plug of normal cylinder. Perform IGNITION SPARK TEST on spark plug newly installed in malfunction-detected cylinder. Is test result satisfactory? | Replace spark plug in malfunction-detected cylinder. See SPARK PLUG REMOVAL AND INSTALLATION . | Go to Step 6. |
| 6 | Ignition spark test 3 Replace ignition coil assembly of malfunction-detected cylinder with the ignition coil assembly of normal cylinder. Perform IGNITION SPARK TEST on spark plug in malfunction-detected cylinder. Is test result satisfactory? | Replace ignition coil in malfunction-detected cylinder. See IGNITION COIL ASSEMBLY REMOVAL AND INSTALLATION . | Go to Step 7. |
| 7 | Ignition coil assembly drive circuit check Check drive circuits of each ignition coil assembly for open, short and poor connection. Are circuits in good condition? | Go to Step 8. | Repair or replace malfunctioning part. |
| 8 | Ignition coil assembly power supply and ground circuit check Check power supply and ground circuits of ignition coil assembly for open, short and poor connection. Are circuits in good condition? | Substitute a known-good ECM and recheck. | Repair or replace malfunctioning part. |
TROUBLESHOOTING REFERENCE CHART
Scheme 3
- Remove spark plugs. See «SPARK PLUG REMOVAL AND INSTALLATION»(ref-514577-S39604449802012112100000) .
- Inspect spark plugs. See «SPARK PLUG INSPECTION»(ref-514577-S27594285522012112100000) . WARNING: If this test is performed without disconnecting the injector couplers, a spark from a plug may ignite fuel vapor coming out of the spark plug holes during the test, causing a fire or explosion. Be sure to disconnect the injector couplers from the injectors before performing this test. NOTE: For identification of each cylinder, refer to «PRECAUTIONS FOR IDENTIFICATION OF CYLINDER»(ref-514565-S07044014712012112100000) .
- Disconnect injector connectors.
- Connect ignition coil connector (3) to ignition coil assembly.
- Connect spark plug (2) to ignition coil assembly (1), and ground spark plug.
- Crank engine and check if each spark plug produces sparks.
- If any spark plug does not produce sparks, check ignition system. See «IGNITION SYSTEM CHECK»(ref-514577-S32792500152012112100000) .