The fuel pump is located above the fuel tank, and is controlled by the Engine Control Module (ECM) via the fuel pump relay.
Operation
Power Distribution
Feed from the positive battery terminal (C0192) is supplied to the following on an N wire.
- Fusible link 5
- Fuse 4
- Fuse 5.
All are located in the under seat fuse box (C0632).
Fuse 4 (C0573) provides a constant battery feed to the fuel pump relay (C0730) on a PW wire. Fuse 5 (C0574) provides a feed to the main relay (C0063) and the inertia switch (C0123) on NLG wires. Fusible link 5 (C0570) provides a feed to the ignition switch (C1043 on LHD, C0028 on RHD) on an NW wire.
When the ignition switch is turned to the 'ignition' position, current flows across the switch (C1732 on LHD, C0094 on RHD) to fuse 11 of the passenger compartment fuse box (C0580) on a W wire. Fuse 11 (C0580) provides an ignition feed to the ECM (C0658) on a WG wire.
Main Relay
The main relay coil (C0063) is provided a constant battery feed via the inertia switch (C0123) on an N wire. When the ECM (C0658) receives an ignition switch feed from fuse 11 of the passenger compartment fuse box (C0580), it provides an earth path for the main relay coil (C0063) on a UR wire. The energised main relay (C0063) is now able to provide a feed to the fuel pump relay (C0730) and back to the ECM (C0658) on a series of NO wires.
Fuel Pump Relay
The fuel pump relay coil (C0730) receives a feed from the energised main relay (C0063) on an NO wire. If the ECM (C0658) has received the correct re-mobilisation signal from the anti-theft alarm ECU, it provides an earth path for the fuel pump relay coil (C0730) on a UP wire.
The energised fuel pump relay (C0730) is now able to provide a feed to the fuel pump (C0114 on 90 models, C0115 on 110 vehicles, C2063 on 130 vehicles) on a WP wire. The fuel pump (C0114 on 90 models, C0115 on 110 vehicles, C2063 on 130 vehicles) is earthed on a B wire.
Fuel Tank Sender Unit
The fuel tank sender unit (C0114 on 90 models, C0115 on 110 vehicles, C2063 on 130 vehicles) is provided a feed by the energised fuel pump relay (C0730) on a WP wire. The output voltage supplied by the sender to the instrument pack (C1061) on a GB wire varies in relation to fuel level. The sender unit (C0114 on 90 models, C0115 on 110 vehicles, C2063 on 130 vehicles) is earthed on an SB then B wire.