Toyota DTC P1300

A DIS (Direct Ignition System) 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 one 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 2 spark plugs. In one of the spark plugs, the spark passes from the center electrode to the ground electrode and in the other plug the discharge is in the opposite direction, i.e. from ground to center electrodes.

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.


Ignition Coils and Igniter Circuit


Beginning with the 2001 model year on 1 ignition coil/igniter per cylinder engines, the ECM fail-safe will turn Off the Fuel Injector if there is no IGF signal for that cylinder and if engine conditions (such as load and temperature) are sufficient to damage the catalytic converter...
...If there is no IGF signal on engines before 1998 model year, the ECM will enter fuel fail-safe and turn Off all the Fuel Injectors (P1300 series DTCs).

Toyota Direct Ignition System (DIS)
Toyota Direct Ignition System (DIS)
IGT and IGF Inspection using an oscilloscope

В этом топике форума al tech page описан пример диагностики и ремонта при DTC P1305, приведены реальные осциллограммы напряжений на контактах катушек зажигания DIS, рассмотрены алгоритмы формирования сигнала IGF (Ignition Frrdback) и другие методы контроля качества воспламенения воздушно-топливной смеси.

IGF Detection using CEMF IGF Detection throug Primary Current

WaveformToyota Igniter IGF Signal as function of IGT duration by using Selfmade Spark Checker

Checking IGT, IGF, and Coil Current of Toyota Independent DIS Ignition Coil with Integrated Igniter

And Results. Duration of IGT vs. IGF vs. Coil Current on Toyota Independent DIS Ignition Coil with Integrated Igniter

Toyota Igniter Measuring of Ignition Coil Current
IGT and bad IGF Waveform on 2AZ-FE
IGT and IGF Waveform on 2AZ-FE

Офф. В части современных двигателях (Daihatsu Storia/Toyota Duet, Lexus LFA, Mazda3/Mazda6, etc.) для анализа "качества" воспламенения смеси используются не IGF, а сигнал тока ионизации (Ignition Coil witch Ion Current detection)