Thought I'd post this in case anyone searches usenet.
The blower is in a circuit from the alternator via the ignition switch. It will only work when the ignition is on And the engine is running. This makes some sense, as you don't want it sapping power while you're trying to start the car.
If the heater blower stops functioning, the fault is normally with the ignition switch; the thing behind the key. The correct solution is to replace the ignition barral and switch, which, if you have an old car, is disproportionately expensive, =A3200 even.
But there is a cheat. There are three circuits run from the ignition switch; the blower- two brown wires , and two others. (I cant remember the colours. one pair is yellow, maybe?? not important) So it is like three switches in one.
- Tap in to one of the other circuits as follows:- Remobe the cover below the steering wheel. (note dipswitch attached to that cover) Cut the plug from the two brown wires from the blower, and strip the exposed ends. Strip rubber from the middle one of the other pairs of wires without cutting.(Colours?? yellow and something???)
Buy a free standing relay. Attach that so that when the yellow wires become active the relay closes. Attach the brown wires so that they are connected together when the relay closes. When you put the cover back, note that the headlight dip switch is still connected to it. It'll fall off while youre working and is easy to forget. =2E.................................... Thats it. For =A35 you get a bit more life out of the ignition switch. =2E...................................
An easier way is to cut the two brown wires, strip them, and tie them together, but this is rubbish because it means you have to remember to turn the blower off every time you get out the car, or it'll keep running. =2E............................
Tony