WIRING MODIFICATIONS REQUIRED WHEN FITTING SMITHS CLASSIC RANGE INSTRUMENTS TO YOUR DAX

Information from DJ Sportscars

DAX wiring looms are designed to be used in conjunction with the wiring format utilised by Stewart-Warner and other like-minded instrument manufacturers. Some instruments (e.g. the Smiths Classic Range) operate on a slightly different principle and require minor wiring loom modifications for correct operation. These modifications are applicable to the wiring of fuel gauges, temperature gauges and electrically operated oil pressure gauges only, and involve a change in the earth lead requirement and, in the case of fuel level and temperature gauges, the need to include a voltage regulator unit.

The DAX loom includes three wires for each of these gauges:

• an earth wire - coloured black
• a sender wire - coloured green/black (fuel)
• a sender wire - coloured green/blue (temperature)
• a sender wire - coloured grey (oil pressure)
• a + feed wire - coloured green

Instructions to allow the use of instruments of the Smiths Classic Range type:

The black earth wire

The fuel, temperature and oil pressure instruments of the Smiths Classic Range type do not require an earth connection. The black wire provided for each gauge should therefore be insulated and tied back.

The sender wire

The sender wire requirement is unaffected by the change of instruments. As with instruments of the Stewart-Warner design, the instrument's sender wire should be attached to the gauge terminal provided.

The green positive feed wire

Oil Pressure gauge:

The oil pressure gauge, in common with instruments of the Stewart-Warner design, is designed to operate from a 12 volt supply. The green positive feed wire provided can therefore be fitted directly to the appropriate gauge terminal.

Fuel & Temperature gauges

Fuel and temperature gauges of this type are designed to run at a reduced voltage (10 volts). To achieve this, a voltage regulator unit must be added to the system.

1. Secure the voltage regulator in a suitable location close to the instruments, ensuring that the body of the unit is properly earthed.
2. Attach the green positive feed wire/s for the instrument/s concerned to the voltage regulator's input terminal, marked 'B'.
3. Run wire/s from the regulator's output terminal, marked 'I', to the terminal provided on each of the gauges.