The choke control, controls the choke! On an SU carb this control has 2 functions. The first quarter to half inch of travel gives you an increased idle speed only and helps keep the engine running when idling under load. As you pull it further than that it will gradually enrich the fuel mixture. As said above this is intended as a starting aid only. If you have to use the choke to drive normally, the engine is not tuned properly.
The other control cable operates the heater valve. In a car of this age you often don't actually have a cable to control this, you have to do it under the bonnet. The cable will be pushed in for hot and pulled out for cold in your car.
If the black knob you can't identify operates as a plunger it is the screen washer pump. It's not powered, you have to pump it.
The toggle switch under the clocks switches the instrument lighting. It only works when the headlamps are on but gives you the option of turning the gauge lighting off if it's distracting you at night.
The toggle switch on the heater should operate the heater fan I think.
<<OK I've seen the photo now. The control cable with a fire logo on it is the heater cable and the other black knob is indeed the washer pump.>>
<<Regarding the heater, is there an electrical switch or are you referring to the flap valve labelled 'off, screen, car'?>>
Edited by Dan, 26 September 2009 - 11:34 PM.