See Figures 1 and 2
For information on understanding electricity and troubleshooting electrical circuits, please refer to Chassis Electrical of this guide.
The EZ115K, EZ116K, EZ129K, and REX-1 ignition systems, used on Coupe, 240, 700 series, 1993-94 850, and 940 models are like most engine management systems currently in use, in that ignition functions are closely integrated with the fuel system. Various sensors feed information to an on-board computer which makes necessary adjustments.
The EZK ignition systems are used on vehicles utilizing Bosch LH-Jetronic electronic engine controls. The REX-1 system is used on vehicles with the Bendix Regina electronic engine control system. Both systems have separate control modules for the ignition and engine controls. The inputs are similar on both; knock sensor, crankshaft position sensor, engine coolant temperature sensor, throttle position sensor or switch, and inputs from the electronic engine control module.