circuitry 80 lines 51 52 and 53 provide connections between the engine sensors 50 and the fault indicator circuit 70 line 54 is a connection between the engine sensors 50 and the engine control relays circuit 60 the engine control relays circuit is connected to the alarm circuit 90 through lines 61 62 and 63 line 64 connects the engine control relays circuit 60 with the solid state circuitry 80 the engine control relays circuit 60 is also connected to terminal 4 through line 65 the engine control relays circuit is connected to common bus line 100 the fault indicator circuit 70 is connected to the alarm circuit through line 71 and to the solid state circuitry 80 through line 72 the fault indicator circuit 70 and the alarm circuit 90 are connected to a common electrical point 91 through line 73 lines 81 82 and 83 connect the solid state circuitry 80 to the alarm circuit 90 the solid state circuitry 80 is connected to the common bus line 100 the common bus line 100 is connected to point 91 through normally closed relay contacts a2a point 91 connects through normally open relay contacts a2b to ground said relay contacts a2a and a2b are in a single pole double throw configuration with their common electrical point being the common electrical point 91 electrical point 91 is also connected to ground through switch 101 and normally closed contacts 102 in series electrical point 91 is also connected to ground through normally open contacts 103 and contacts 102 in series fig2 a 2b and 2c represent a schematic diagram of the preferred embodiment when placed.