Rear demist switch and cigar lighter

pmansson

pmansson

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I have just had the gear shift console out for repairs. Before installing it again and attaching it to the side panels, I would like to ensure correct electric attachments to the above parts.
On the cigar lighter, does the brown, earth cable attach to the bottom pin or the one above to the side?

Likewise with the rear window demist switch; does the black cable going to the rear window go on the lower or upper pin?
Is is possible to check the function, in a garage, by putting one palm on the heated section and the other on a non-heated section of the rear windscreen?

I am suspicious as the cigar lighter doesn´t work with either cable connection possibility. It stays in the lower position without heating up. The heater coil is new.
Perhaps I have power supply problems from the fusebox to the items or equally, a grounding issue.
All input is much appreciated.
 
I don't have mine out to look out but the cigar lighter polarity matters
if you will plug other things like phone chargers. The brown/earth should have continuity to the outer part of the connector, and the yellow-red to
the inner contact. The fuse for the lighter seems to be dedicated,
so you can check the fuse (5) or for voltage at the inner contact.

For the rear window demist I do not think that polarity matters as it is just
a resistor. The fuse is number 8 and you can check operation by
measuring current through fuse 8. This circuit is not energized when the
key is not in running mode.
 
On the light, the brown pin should go to the side pin; the center pin is for 12 volts - it will work either way but if plugged in backward would would have a 20 amp circuit applying voltage to the aluminum console strip and a nasty accident could happen.

On the demist switch I don't think there is an upper pin. There is a center pin which should have a brown lead; this is ground for the little internal lamp. The outer three pins should have 12 volts in, and the lead to the demist circuit (black?). When the switch is released the three outer pins are all connected together and the internal lamp gets connected as well. So, aside from center and outer, the pin orientation doesn't (shouldn't) matter.

On the lighter make sure that you have power and ground. On mine I had to use a small screwdriver and bend in the brass colored clips at the bottom of the socket (make sure wires are off before doing this). The clips had relaxed out after years of displacement. I also found a new lighter end (coil at bottom) for a few bucks at one of the typical part source (can't recall).

If you need help checking grounds / power send me a PM.
 
I agree on the cigar lighter.
On the rear demist switch, this concerns a 1974 car with the switch where the earlier cars had the wiper speed selector, as on your picture.
However, it seems that the pins can go either way on this one. It´s just power out to the rear window, or not. Ground is at the other end of the rear window.
I was just curious as to whether the ON position caused the heating section to be warm enough to be felt by a hand on this section and comparing it to the "cold", other hand on the rest of the screen.
 
I doubt you can confirm the demist function with your hand because the demist only uses about 30-50 watts over a large area. I would probably test it in a crude manner. If you turn on the demist there should be a few amps flowing. I would simply carefully remove the connector at the window and look for small sparks as the connector is touched to the plug. The voltage is low and the sparks will be small but they will happen if the demist is working. If you do this make sure there are no open fuel sources close by!
 
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