Grand Caravan FWD V6-181 3.0L SOHC (1993)
Ignition Hall Effect Sensor: Description and Operation
LOCATION
Housed in distributor.
PURPOSE
The Powertrain Control Module (PCM) uses this input to determine engine speed and crankshaft position, and adjusts ignition timing, fuel
injection, and idle speed accordingly.
OPERATION
Pick-up generates pulses when slots pass between Light Emitting Diodes (LED's) and photo diodes.
Optical Distributor Top View
Optical Distributor Cut Away View
THEORY
A disk, with 2 sets of slots, spins at half engine speed, between two LED/photo diode pairs (optical sensors).
The outer or "high data rate", slots pass through the corresponding sensor at a rate of 1 slot per 2 degrees of crankshaft rotation.
The inner, or "low data rate", set of 6 slots, correspond to top-dead-center for each piston.
