I've been looking at this, and as far as I can see it's fairly simple to get the folding working, and even to auto-fold with the ignition.
The motors simply need 12v in one direction to fold and reverse the current to unfold.
This could be achieved using a pair of relays to reverse the flow and either a switch or a relay to operate them manually or automatically.
If you automated them, then you could add a switch to fold them manually if required.
At its most basic, two relays and an ignition switched feed would give you auto-fold mirrors, although they would stay live all the time, and 'could' result in a flat battery.
The most basic system would need two SPDT, 5 pin relays, a permanent 12v supply, a switched supply (ignition or manual) and an earth.
I will ignore the switched supply and describe the wiring for the mirrors. There are two wires from each mirror but you can splice them so that only two wires arrive at the relays, not four.
So two wires from the mirrors arrive at two relays and one wire connects to each relay, on the common terminal labelled 30 (3).
On one relay the NC (normally closed) terminal, labelled 87a (4), is connected to the permanent 12v supply and the NO (normally open) terminal, labelled 87 (5), is attached to earth.
On the other relay the NC terminal is connected to earth and the NO is attached to the permanent 12v supply. This is the folded position.
When power is applied to the coil, terminals 85,86 (1,2), via the switched supply, the relays switch over, reversing the flow and the mirrors unfold. Cut the switched power and the mirrors fold.
I believe the mirrors have limit switches, so the motors stop when fully open or closed.
The circuit could be enhanced, by adding a switch for manual control.
The wires on the mirrors can be picked up on the connector in the door and would only need a light cable to connect to the relays, speaker wire should be sufficient, and would
be easy to route through the car.
Can anyone see a problem with that, or draw a diagram to illustrate it? Any improvements?
stealthe
Edited to add terminal no's for pug mini relays (1-5 in brackets) as seen here
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