The instrument pack relays information to the driver via the instrument pack. The instrument pack contains warning lamps and analogue gauges. The warning lamps illuminate in one of four colours, which indicate the level of the warning as follows:
- Red - Warning
- Yellow - Caution
- Green - System operative
- Blue - Headlamp main beam operative.
Operation
Power Distribution
Feed from the positive battery terminal (C0192) is supplied to fusible link 5 and fusible link 1 of the under seat fuse box (C0632) on an N wire. Fusible link 1 is connected in series with fusible link 2, which is also located in the under seat fuse box. Fusible link 2 (C0570) is connected to fuse 30 of the passenger compartment fuse box (C0595) by an NK wire. Fuse 30 (C0595) provides a constant battery feed to the engine immobilisation warning lamp (C1060) and the speedometer (C1060) on PN wires.
Fusible link 5 (C0570) is connected to the ignition switch (C1043 on LHD, C0028 on RHD) by 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 15 of the passenger compartment fuse box (C0580) on a W wire. Fuse 15 (C0580) provides an ignition feed to the following on WG wires:
- The fuel gauge (C1054)
- The engine coolant temperature gauge (C1052)
- The speedometer (C1060)
- The low fuel warning lamp (C0233)
- The differential lock warning lamp (C0233)
- The oil pressure warning lamp (C0233)
- The ignition/no charge warning lamp (C0236)
- The transmission oil warning lamp (C0233)
- The ABS warning lamp (C0230)
- The traction control warning lamp (C0230)
- The handbrake/low brake fluid warning lamp (C0234)
- The transmission oil warning lamp (C0234).
Fuel Gauge
Fuse 15 of the passenger compartment fuse box (C0580) provides an ignition feed to the fuel gauge (C1054) on a WG wire. The fuel tank sender unit provides a feed to the instrument pack (C1061) on a GB then LGB wire.
The voltage supplied to the instrument pack varies in relation to fuel level. The fuel gauge (C1054) is earthed on a B wire.
Engine Coolant Temperature Gauge
Fuse 15 of the passenger compartment fuse box (C0580) provides an ignition feed to the engine coolant temperature gauge (C1052) on a WG wire.
Td5
The Engine Control Module (ECM) (C0658) provides a 5 V feed to the Engine Coolant Temperature (ECT) sensor (C0169) on a KG wire. As coolant temperature increases, the resistance of the sensor decreases. By measuring the resistance of the sensor on a KB wire, the ECM can determine ECT. The ECM (C0658) then provides a Pulse Width Modulated (PWM) ECT signal to the gauge on a GU then LGU wire. The gauge (C1052) is earthed on a B wire.
300Tdi
The Engine Coolant Temperature (ECT) sensor (C0169) provides an ECT signal to the instrument pack (C1052) on a GU then LGU wire. The gauge (C1052) is earthed on a B wire.
Speedometer
The speedometer (C1060) receives a constant battery feed from fuse 30 of the passenger compartment fuse box (C0595) on a PN wire. The speedometer (C1060) also receives an ignition feed from fuse 15 of the passenger compartment fuse box (C0580) on a WG wire. The speedometer (C1060) is earthed on a B wire.
The speed transducer (C0195) provides a square wave, pulsed speed signal to the instrument pack (C1060) on a BR wire. The instrument pack uses this signal to drive the speedometer. The speedometer also doubles the frequency of pulses (from 4100 per mile to 8200 per mile) and provides an output to the ECM (C0658 - Td5 vehicles only) and the overspeed ECU (C1311 - Gulf specification vehicles only) on YK wires.
The anti-theft alarm LED is also contained within the speedometer, and is driven by the anti-theft alarm ECU (C1980 on LHD, C0057 on RHD) on a K wire.
Warning Lamps
The warning lamps operate as follows:
- Illumination of the low fuel warning lamp (C0233) is controlled internally within the instrument pack by the speedometer. For more information, refer to the Fuel Gauge section earlier.
- Illumination of the differential lock warning lamp (C0233) is controlled by differential lock unit (C0306) on a BU wire. When differential lock is selected, the switch contacts within the unit close creating a path to earth (C0307) on a B wire. Current from fuse 15 of the passenger compartment fuse box (C0580) is now able to flow across the bulb.
- Illumination of the oil pressure warning lamp (C0233) is controlled by the oil pressure switch (C0187) on a WN wire. When low oil pressure is detected by the switch, the switch contacts close creating a path to earth. Current from fuse 15 of the passenger compartment fuse box (C0580) is now able to flow across the bulb.
- Illumination of the ignition/no charge warning lamp (C0233) is controlled by the alternator (C0236 on Td5 vehicles, C0185 on 300 Tdi vehicles) on an NY wire. When the alternator is not producing an output voltage, current is able to flow across the bulb to earth via the alternator. When the alternator outputs a voltage equal to that supplied by fuse 15 of the passenger compartment fuse box (C0580), the lamp will extinguish as the potential difference across the lamp is 0 volts.
- Illumination of the transmission oil warning lamp (C0230) is controlled by the transmission oil temperature switch (C0686) on an SR wire. When transmission oil temperature exceeds the recommended limits, the switch contacts close creating a path to earth (C0687) on a B wire. Current from fuse 15 of the passenger compartment fuse box (C0580) is now able to flow across the bulb.
- Illumination of the ABS warning lamp is controlled by the ABS ECU. If the ABS ECU (C0504) detects a fault in the system, it provides a feed to the ABS warning lamp (C0230) on an RS wire. This triggers a series of transistors and diodes within the instrument pack to allow current from fuse 15 of the passenger compartment fuse box (C0580) to flow across the bulb. The bulb is earthed via the instrument pack on a B wire. NOTE: If ABS isn't fitted, a shorting link is fitted to the instrument pack between C0234-6 and C0234-10. This link prevents the ABS warning lamp illuminating.
- Illumination of the Traction Control (TC) warning lamp (C0230) is controlled by the ABS ECU (C0504) on a YS wire. When TC is active (or if the ABS ECU detects a TC fault) the ABS ECU provides an earth path, allowing current from fuse 15 of the passenger compartment fuse box (C0580) to flow across the bulb.
- Illumination of the handbrake/low brake fluid level warning lamp (C0230) is controlled by the brake fluid level switch (C1725 on LHD, C0026 on RHD), and the handbrake switch (C0091). If brake fluid level is too low, the brake fluid level switch contacts (C1726 on LHD, C0031 on RHD) will close, creating an earth path for the bulb on a B wire. If the handbrake is applied, the switch contacts (C0091) close creating an earth path for the bulb. NOTE: If ABS isn't fitted, a shorting link is fitted to the instrument pack between C0234-9 and C0234-13. This enables the handbrake/low brake fluid warning lamp to operate correctly in the absence of an EBD signal.
- Illumination of the main beam warning lamp (C0233) is controlled via the column switch (C1739 on LHD, C1042 on RHD) on a UW wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the RH direction indicator warning lamp (C0233) is controlled via the column switch (C1739 on LHD, C1040 on RHD) on a GW wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the rear fog lamp warning lamp (C0233) is controlled by the fog lamp ECU (C1724 on LHD, C0543 on RHD) on a RY wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the hazard warning lamp (C0233) is controlled by the hazard warning relay (C0547) on a BR wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the engine immobilisation warning lamp (C0233) is controlled by the anti-theft alarm ECU (C1980 on LHD, C0057 on RHD) on an O wire.
- Illumination of the Heated Rear Window (HRW) warning lamp (C0233) is controlled via the HRW relay (C0044) on a WB wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the trailer warning lamp (C0233) is controlled via the hazard warning relay (C0547) on an LGP wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the engine management warning lamp (C0233) is controlled by the Engine Control Module (ECM) (C0658) on an RS wire. The ECM provides an on/off signal to the warning lamp to control its flashing sequence. For more information, refer to the Engine Management System - Td5 section of the workshop manual.
- Illumination of the glow plug warning lamp (C0233) is controlled by the ECM (C0658) on Td5 vehicles, or the glow plug ECU (C0190) on 300 Tdi vehicles. When the ignition switch is turned to the 'ignition' position, a feed is supplied to the warning lamp on a BY wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the LH direction indicator warning lamp (C0233) is controlled via the column switch (C1739 on LHD, C1040 on RHD) on a GR wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the side lamp warning lamp (C0233) is controlled via the lighting switch (C1082 on LHD, C0041 on RHD) on an R then RB wire. The lamp (C0230) is earthed on a B wire.
- Illumination of the water filter warning lamp is controlled by the water filter sensor. When water collects in the bottom of the fuel filter, the sensor (C0735 on 90 vehicles, C1978 on 110 vehicles, C2064 on 130 vehicles) provides a feed to the warning lamp (C0230) on an OG wire. The lamp (C0234) is earthed on a B wire.
- Illumination of the overspeed warning lamp is controlled by the overspeed ECU (C1311) on a BK wire. NOTE: The overspeed warning lamp is only fitted to Gulf Market Specification vehicles.