Instruments (Instrument pack): Description and operation

INSTRUMENT PACK

Petrol model illustrated

The instrument pack is a totally electronic device receiving electrical signals from sender units and transposing them into analogue gauge readouts.

Speedometer

The speedometer is electronic and contains a six digit odometer and a four digit trip distance readout up to 999.9. The speedometer is driven by a transducer mounted in the gearbox and is calibrated to 990.5 rev/min at 60 mph (615.6 rev/min at 60 km/h) on ’K’ series models (not VVC) , or 1000 rev/min at 60 mph (621.5 rev/min at 60 km/h) on VVC models.

Tachometer

The tachometer signal consists of 2 pulses per revolution and is taken from the ignition coil.

The tachometer maximum scale reading is 8000 rev/min for all models.

Instrument illumination

Instrument illumination in the form of backlighting is provided by 3 x 14v, 3.4w t10 bulbs.

Fuel gauge

The fuel gauge pointer will display level of fuel in the tank when the ignition was last switched off.

When the gauge unit float is at its lowest point, indicating an empty fuel tank, the resistance to earth is at its greatest. The resistance value to fuel gauge position is: