Contactless ignition system [Toyota RAV4 XA10]

Models from 1996 to 1998 used a conventional contactless ignition system consisting of an ignition switch, battery, distributor and ignition coil, electronic control module (ECM), crankshaft angle sensor, spark plugs and wires.

The Electronic Control Module (ECM) controls the ignition timing based on signals from sensors that monitor engine operating conditions such as engine speed, air flow, coolant temperature, etc., under all operating conditions. The ECM is located on the right side of the engine compartment.

This contactless ignition system includes an inductive sensor located inside the ignition distributor, an ignition coil mounted on the intake manifold near the ignition distributor, and a switch located in the engine compartment.

On models from 1998 to 2001, the switch and ignition coils were made as a single unit, mounted on a bracket on the intake manifold.

Models from 2001 onwards featured ignition coil/commutator units on each cylinder, directly on the spark plugs, eliminating the need for high-voltage wires.

On models from 1998 to 2001, the contactless ignition system consists of a camshaft position sensor, a crankshaft angle sensor, ignition coils (one coil per 2 cyl.), the ignition coil and the power control module (PCM) are housed in a single unit and mounted on the front of the engine. Based on signals from the camshaft position and crankshaft angle sensors, the engine control unit identifies the cylinder and sends a control pulse to the commutator to supply a spark to the corresponding cylinder. Each ignition coil actually consists of two separate high-voltage windings, each supplying a spark to two cylinders (one to cylinders 1 and 4, and the other to cylinders 2 and 3). An ignition pulse is sent to two spark plugs simultaneously for each engine cycle: one on the compression stroke and one on the exhaust stroke. The spark on the exhaust stroke has no effect on engine operation and is therefore wasted. The powertrain control module (PCM) uses signals from various sensors to calculate the required ignition timing and the energy storage time in the ignition coil.

On 2001 and later models, the contactless ignition system consists of a camshaft position sensor, a crankshaft angle sensor, an ignition coil/ignition switch/spark plug assembly mounted on each cylinder, and the engine control module (PCM). Based on signals from the camshaft position and crankshaft angle sensors, the PCM identifies the cylinder and sends a control pulse to the appropriate ignition coil/ignition switch/spark plug assembly, as well as calculates the required ignition timing and the energy storage time in the ignition coil.