Starting - operation

When the alternator outputs a voltage equal to that supplied by the battery, the warning lamp is extinguished as the potential difference across the lamp is 0 volts. The diode between the alternator and warning lamp prevents reverse flow.

The regulator functions as an electronic control switch on the earth side of the field coils. The regulator rapidly switches the earth circuit off and on to control the generated voltage and current to safe limits.

If the battery is in a low state of charge or current draw from the electrical system is high and causes a voltage drop, the alternator charges at its maximum rate until 14 volts is generated. As battery voltage rises, the generator current output reduces.

STARTING - OPERATION

Feed from the positive battery terminal is connected to the engine compartment fuse box (C632-1) by a brown wire. Current passes through fusible link 2 and fusible link 3, which are connected in parallel. Fusible link 2 (C907-2) is connected to the ignition switch (C028-1) by a brown wire.

When the ignition switch is turned to the "crank" position, power flows across the switch (C090-1) to the starter relay coil (C151-85) on a white/red wire. Current then flows from the starter relay (C151-86) to the alarm ECU (C057-10) on a black/orange wire. Assuming the alarm ECU has received the correct code from the RF handset, it will complete the path to earth (C057-11) on a black wire and energize the starter relay.

Power from fusible link 2 (C907-2) can now flow across the starter relay switch and onto the engine immobilisation ECU (C863-6). Again, assuming the alarm ECU has received the correct code from the RF handset, it will inform the engine immobilisation ECU (C863-10) to provide a feed to the starter motor solenoid (C179-1) on a black wire. This feed will energize the solenoid, allowing a positive feed from the battery to flow across the solenoid (C178-1) and power the starter motor. An earth is provided by the starter motor.