Basic TCI-H Ignition

Fig. 6 Component Layout - CIS/CIS-E:

This system consists of a Hall generator in the distributor, electronic control unit, idle stabilizer (on California models), specially calibrated secondary ignition components, and related wiring.
The Hall generator consists of a semiconductor layered on magnetic material, permanent magnet, and a slotted umbrella type rotor which passes between the magnet and semiconductor. During operation, constant current flows through the semiconductor, and exposure to the permanent magnet field induces voltage across the semiconductor called Hall effect. This Hall effect voltage is transmitted to an electronic control unit which controls ignition timing and spark duration.
The rotor, attached to the distributor shaft, rotates in the air gap between semiconductor and magnet, blocking the magnetic field. When the magnetic field is blocked, no Hall effect voltage is transmitted to the control unit and signal voltage in the control unit is high, charging the coil primary circuit. When a rotor slot is in the air gap, Hall effect voltage is transmitted to the control unit and signal voltage is low. The control unit then opens the coil primary circuit inducing secondary ignition voltage. The control unit limits system current and controls dwell time (coil saturation) depending upon battery voltage, engine RPM and temperature.
The idle stabilizer is connected in the circuit between the Hall generator and control unit. The stabilizer senses RPM drop and alters ignition timing to compensate for varying engine loads. The stabilizer only operates at engine speeds below 1000 RPM.