740 L4-2.3L SOHC VIN 88 B230F (1985)
System Relay: Description and Operation
Sent by the fuel injection ECU:
The system relay (located in center console behind the ash-tray) provides current to the fuel pumps, suppressor relay, air mass meter, oxygen sensor
pre-heating resistor and to other ECU controlled functions or components.
The fuel injection ECU controls the relay ground connection. When ground is supplied, the system relay is activated and currant can flow to all the
related components. If the ground connection is interrupted, no current can reach the components.
