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Main Relay (Computer/Fuel System)|Testing and Inspection > < Main Relay (Computer/Fuel System)|Bendix
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Main Relay (Computer/Fuel System): Description and Operation
Bosch

Sent by the fuel injection ECU:

PURPOSE

The system relay provides current to the fuel pumps, idle air valve, mass air flow sensor, suppressor relay, oxygen sensor pre-heating resistor and
to other ECU controlled functions or components.

LOCATION

Located in center console behind the ash-tray.

OPERATION

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. 

Main Relay (Computer/Fuel System)|Testing and Inspection > < Main Relay (Computer/Fuel System)|Bendix