DTC P0351 Ignition Coil "A" Primary / Secondary Circuit; DTC P0352 Ignition Coil "B" Primary / Secondary Circuit; DTC P0353 Ignition Coil "C" Primary / Secondary Circuit; DTC P0354 Ignition Coil "D" Primary / Secondary Circuit; DTC P0355 Ignition Coil "E" Primary / Secondary Circuit; DTC P0356 Ignition Coil "F" Primary / Secondary Circuit; DTC P0357 Ignition Coil "G" Primary / Secondary Circuit; DTC P0358 Ignition Coil "H" Primary / Secondary Circuit: Description

A Direct Ignition System (DIS) is used on this vehicle.

The DIS is a 1-cylinder ignition system which ignites one cylinder with one ignition coil. In the 1-cylinder ignition system, the one spark plug is connected to the end of the secondary winding. High voltage generated in the secondary winding is applied directly to the spark plug. The spark of the spark plug passes from the center electrode to the ground electrode.

The ECM determines the ignition timing and outputs the ignition signals (IGTs) for each cylinder. Using the IGTs, the ECM turns the power transistor inside the igniter on/off, which switches on/off current to the primary coil. When current to the primary coil is cut off, high voltage is generated in the secondary coil and this voltage is applied to the spark plugs to create sparks inside the cylinders. As the ECM cuts current to the primary coil, the igniter sends back ignition confirmation signals (IGFs) for each cylinder ignition to the ECM.

Fig 1: Ignition Coil Circuit Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 2: IGT Signal Waveform Graph

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Reference: Inspection using an oscilloscope.

While cranking or idling the engine, check the waveform between terminals IGT1 to IGT8 and E1, and IGF1 to IGF2 and E1 of the E2, E3 and E4 ECM connectors.