S60 L5-2.4L VIN 64 B5244S6 (2003)
Main Relay (Computer/Fuel System): Description and Operation
Main Relay (System Relay)
The function of the main relay (system relay) is to supply certain components with voltage.
The relay is mechanical and has a closing function. In the rest position the circuit in the relay is open.
The main relay terminals (#30 and #86) are supplied with voltage by the battery. When the ignition key has been turned and the Engine Control Module
(ECM) is powered, the terminal (#85) on the main relay is grounded by the Engine Control Module (ECM).
When the terminal (#85) is grounded, the relay is activated and a number of components are powered via the relay terminal (#87).
The engine control module (ECM) can diagnose the main relay.
The main relay is in the relay/fuse box in the engine compartment.