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DCC Trip Computer

DCC Trip Computer Diagrams:




DCC Trip Computer Components:




Locations of components

3 Earthing point, facia
At the left-hand front speaker socket

16 Instrument lighting rheostat
On the left-hand side of the facia

20 Ignition switch
On the right-hand side of the steering column

22A Fuse board
Behind the access panel in the glove compartment

57 Three-pole connector
At the speedometer

110 Tachometer
In the combined instrument

122 Eight-pole connector
One behind the combined instrument
Two on the DCC trip computer

132 Sensor for speed transmitter
In the speedometer, in the combined instrument

159 Distribution terminal +15
In the electrical distribution box behind the glove compartment

210 EDU1/EDU2 trip computer
In the combined instrument

230 Distribution terminal +30
In the electrical distribution box behind the glove compartment

241 DCC trip computer
In the centre of the facia

244 Two-pole connector
Behind the DCC trip computer

286 Outdoor temperature sensor for the trip computer
Behind the front spoiler on the left-hand side




Operation
A DCC (Driver/Co-driver Computer) provides the following functions:

Time functions
Clock
Elapsed time (from starting)
Stopwatch
Alarm

Trip functions
Average speed
Trip recorder
Distance to destination
Speed warning

Temperature functions
Outdoor temperature
Timer for interior heater

The trip computer is operated by means of the following buttons located below the display.



The buttons are also used to select the units (e.g. km or miles) to be used for displaying information. The operation of the DCC trip computer and other information are contained in section 3:1 of the Service Manual, Electrical system, Instruments.

A light sensor and two buttons - R and INFO - are fitted at the bottom of the DCC.

The purpose of the sensor is to control the brightness of the display automatically under daylight conditions. Under conditions of darkness, the brightness can be control led by means of the instrument lighting rheostat, located on the facia. Buttons R and INFO are used for the EDU trip computer. These are connected to EDU 210, together with the brightness control wiring, across a separate connector (122).

DCC trip computer 241 is supplied from fuse 17 (constant supply) and from fuse 13 when the ignition switch is in the drive position.

The trip computer requires information from speedometer 132 to calculate and display the trip functions. The signal is fed across connector 122, to which the EDU trip computer is connected.

Information for the temperature functions is obtained from outdoor temperature sensor 286, which is located behind the front spoiler. Note that the prevailing outdoor temperature is not displayed on the EDU II when the DCC is fitted.

An interior heater (if fitted) may be started automatically, for example in the morning and evening, using the two timer functions of the trip computer. The heater is controlled across a special connector unit, which is connected to pins3and 7 of the trip computer via two-pole connector 59. The time displayed on the DCC is the time at which the interior of the car will be heated to the desired temperature.

Fault-tracing hints
The trip computer is activated by turning the ignition switch to the drive position.

1. Check fuses 13 and 17 and check that the supply to them is live.
2. Check that the supply to pins 1 and 6 of the trip computer is live.
3. Check that the contact faces of the connectors are intact and clean. This is important since the currents flowing through the connectors are small.
4. Check the wiring and earth connections.
5. Check for voltage at terminal 1 of sensor 132.

NOTE:
Earth cable 778 SV/VT when fitting a petrol-fired (GEH) heater. Do not earth cable 778 SV/VT when fitting an electrically-operated (EEH) heater.

Do not earth cable 774 BL under any circumstances.