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: Description

HINT:

These DTCs indicate malfunctions relating to the primary circuit.
If DTC P0351 is set, check the No. 1 ignition coil circuit.
If DTC P0352 is set, check the No. 2 ignition coil circuit.
If DTC P0353 is set, check the No. 3 ignition coil circuit.
If DTC P0354 is set, check the No. 4 ignition coil circuit.
If DTC P0355 is set, check the No. 5 ignition coil circuit.
If DTC P0356 is set, check the No. 6 ignition coil circuit.

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

The DIS is a 1-cylinder ignition system in which each cylinder is ignited by one ignition coil and the spark plug is connected to the end of each secondary wiring. A powerful voltage, generated in the secondary wiring, is applied directly to each spark plug. The sparks of the spark plugs pass from the center electrode to the ground electrodes.

The ECM (Included in HV control ECU) determines the ignition timing and transmits the ignition signals (IGT) to each cylinder. Using the IGT signal, the ECM turns the power transistor inside the igniter on and off. The power transistor, in turn, switches on and off the current to the primary coil. When the current to the primary coil is cut off, a powerful voltage is generated in the secondary coil. This voltage is applied to the spark plugs, causing them to spark inside the cylinders. As the ECM cuts the current to the primary coil, the igniter sends back an ignition confirmation signal (IGF) to the ECM, for each cylinder ignition.

Fig 1: Ignition Coil Circuit Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DTC DETECTION CONDITION CHART

DTC No.	DTC Detection Condition	Trouble Area
P0351 P0352 P0353 P0354 P0355 P0356	No IGF signal to ECM (Included in HV control ECU) while engine running (1 trip detection logic)	Ignition system Open or short in IGF1 and IGT circuit (1 to 6) between ignition coil and HV Control ECU No. 1 to No. 6 ignition coils HV control ECU

Fig 2: Signal Waveform Graph

Reference: Inspection using an oscilloscope.

While cranking or idling the engine, check the waveform between terminals IGT (1 to 6) and E1, and IGF1 and E1 of the HV control ECU connector.

ITEM CONTENT

Item	Content
Terminals	CH1: IGT1, IGT2, IGT3, IGT4, IGT5, IGT6 - E1 CH2: IGF1 - E1
Equipment Settings	2 V/DIV., 20 ms./DIV.
Conditions	Cranking or idling