Ignition System - Hall Effect: Description
Electronic Spark Control system, used on Chrysler Motors FWD vehicles with 2.2L, 2.5L and 3.9L engines, features a Hall Effect distributor and spark control computer.
The heart of the system is the computer. It provides an infinite number of variable advance curves. This allows ignition of lean air/fuel mixtures according to different modes of engine operation.
The computer contains an electronic printed circuit board which receives signals from various engine sensors. An analysis of these signals determines current engine mode and responds by advancing or retarding ignition timing.
The computer determines when the ignition event is required and signals the ignition coil to produce electrical impulses that fire the spark plugs. Computer is located on the fenderwell.
The connection to other fuel/ignition components is by 10-wire and 14-wire connectors. Up to 5 engine sensors feed information to the computer. These include a vacuum transducer, mounted on the computer housing, the distributor mounted Hall Effect pick-up assembly, engine coolant temperature sensor, carburetor switch and oxygen sensor.
The computerized spark control system eliminates need for vacuum or centrifugal advance units. Hall Effect distributor is connected to the computer system by a 3-terminal connector. See Fig 2. The distributor sends small alternating current signals to the computer as rotor shutter blades enter and leave the gap in the Hall Effect switching unit pick-up assembly.
Carburetor switch senses when engine is at idle. Coolant temperature switch or sensor keeps the computer informed on engine operating temperature. Vacuum transducer informs the computer of engine vacuum (load).