Circuit Description
WARNING: This page is about a different car, the 2003 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
The Direct Ignition System (DIS) is a one-cylinder ignition system which ignites one spark plug connected to the end of the secondary winding of one ignition coil. The ECM determines the ignition timing and outputs the ignition signals (IGT) for each cylinder. Based on the IGT signals, the power transistors in the igniter cut off the current to the primary coil in the ignition coil. High voltage is supplied to the spark plug that is connected to the end of the secondary coil. At the same time, the igniter also sends an ignition confirmation signal (IGF) as a fail-safe measure to the ECM.