Electronic Control Module Operation

Each Dura-Spark II module has 6 wires in 2 connectors. The Red and White wires are ignition feed wires. The White wire is for cranking, and the Red wire provides for normal engine operation. The Red wire circuit contains a 1.1-ohm resistance wire. The current to primary circuit of the ignition coil is turned off and on through Green wire.

The Orange and Purple wires transmit signals to ECM from reluctor (armature) and pick-up coil (stator) in distributor. The Black wire is used to ground ECM through distributor housing.

Electronic control modules of the UIM type, having the third connector, provide for additional spark timing control. This connector receives a signal from the Ignition Barometric Switch, Ignition Timing Vacuum Switch, or the MCU module depending on engine calibration.