P0351
DTC P0351 Igniter Coil "A" Primary/Secondary CircuitCIRCUIT DESCRIPTION
DTC Detecting Condition:
A Direct Ignition System (DIS) has been adopted. The DIS improves the ignition timing accuracy, reduces high-voltage loss, and enhances the overall reliability of the ignition system by eliminating the distributor. The DIS is a 2-cylinder simultaneous ignition system which ignites 2 cylinders simultaneously with 1 ignition coil. In the 2-cylinder simultaneous ignition system, each of the 2 spark plugs is connected to the end of the secondary winding. High voltage generated in the secondary winding is applied directly to the spark plugs. The sparks generated by the 2 spark plugs pass simultaneously from the center electrode to the ground electrode.
The ECM determines ignition timing and outputs the ignition signals (IGT) for each cylinder. Based on IGT signals, the igniter controls the primary ignition signals (IGC) for all ignition coils. At the same time, the igniter also sends an ignition confirmation signal (IGF) as a fail-safe measure to the ECM.
Reference: INSPECTION USING OSCILLOSCOPE
During idling, check the waveform between terminals IGT and E1, IGT2 and E1, IGT3 and E1, and IGF and E1 of the ECM connectors.
HINT: The correct waveforms are as shown in the illustration.
MONITOR DESCRIPTION
Monitor Strategy:
Typical Enabling Conditions:
Typical Malfunction Thresholds:
Component Operating Range:
If the ECM does not receive the IGF after sending the IGT, it interprets this as a fault in the igniter and sets a DTC.
Wiring Diagram:
INSPECTION PROCEDURE
Step 1 - 3:
Step 4 - 6:
Step 7 - 9:
HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, as well as other data from the time when a malfunction occurred.