Trigger inputs are required for the G4X ECU to calculate engine speed as well as engine position. In all but the most basic applications both Trigger 1 and Trigger 2 must be used. These must be connected to crankshaft or camshaft position sensors to provide the required information.

 

·Trigger 1 is used to determine crankshaft position.

·Trigger 2 is used to determine the engines position in the firing order (cam position). Often called the sync signal.

·Digital Inputs may be required for Variable Valve Timing camshaft position sensors (Refer to Digital Inputs Wiring for more information).

 

In applications using direct spark or sequential injection, Trigger 2 must always be driven from a sensor on the camshaft a sensor using a trigger wheel that performs one revolution for each 720 degree engine cycle.

The Trigger 1 and Trigger 2 cables each include two wires surrounded by a braided shield. These have the following functions.

 

 

The braided shield in both cables MUST not be grounded at the sensor end. If the sensor has its own shielded wire connection, make sure this does not connect directly to the engine block.

There are a large number of triggering variants used by different engine manufacturers. The important differences are the type of sensors used, the number of pulses sent from the sensors during an engine cycle and the timing of the pulses in relation to the engine cycle. There are two main types of sensors that are commonly used. It is important that the sensor type is known, as the wiring for each type is completely different.

 

 

See also:

·Reluctor/Magnetic Sensors

·Hall, Optical and Proximity Sensors