Haltech E6X Manual DOS Version - Manual (Page 118)

E6X Manual
118
E.1.2 Reluctor Triggers
A reluctor trigger produces a signal trace that looks like an upward or positive pulse followed
immediately by a downward or negative pulse and then remains flat until the next trigger
tooth passes. These sensors normally only have 2 or 4 connections: trigger positive and
trigger negative (home positive and home negative).
A common reluctor trigger is the 24-1 trigger used on some Toyota engines. This trigger has
4 connections: trigger positive, trigger negative, home positive and home negative. Below is
an example of a Toyota 24-1 trigger; both the single tooth home and the 24-tooth trigger are
shown.
A closer view of the single home tooth shows the shape of the signal:
Notice how the signal rises and then fall below its origin and then rises to settle where it
started. The 24-tooth signal follows the same cycle as that of the single tooth home but does
this at such a frequency that it settling point is not clear.
The reluctor trigger requires signal conditioning that often requires some tuning. The part of
the ECU hardware that conditions the reluctor signal is called a reluctor adaptor and it
converts the reluctor signals shown above to a square waveform similar to that of the Hall