[TTDegs]

Originally Posted by hgt

Some of you dont read the threads properly.
I repeat the manual switch works as normal, in other words the manual switch overides the modification.
So, when you bring the mirrors in manualy they stay in until you manualy exstend them again.

Are these the bits you were referring to hgt?

Originally Posted by hgt

For some reason I am unable to edit my post so I will have to add this here.
I think that a circuit description may help those of you who are building your own units.
CIRCUIT DESCRIPTION
The manual switch simply reverses the polarity of the feed to the motors, therefor all that was required was a relay to do the same thing and then some form of control over the relay from the central locking.
The contacts on the relay are wired so that when the relay is at rest the mirrors are in, when the relay is energized the contacts reverse the polarity of the feed to the motors and the mirrors go out.
So when the mirrors are in, the car is parked and the relay doesn't draw any current, when the mirrors are out the relay is energized and draws 120ma but as the engine is likely to be running thats not a problem, even if the engine wasn't running a car battery would take months to run down with this current drain.
The feed from the central locking is at 12v when the car is unlocked, this is taken to the base of TR1 via D1 protection diode, this turns on TR1 which switches on TR2 and energizes the relay, (the mirrors go out).
When the car is locked the feed from the central locking is at 0v, this turns off TR1 which turns off TR2 the relay drops out and reverses the polarity of the feed to the motors so the mirrors come in.
Now for the clever bit, When the ignition switch is in position 2 the feed from pin 8 of the mirror switch plug is at 12v in one position and 0v or chassis in the other.
By feeding this to the base of TR2 the manual switch takes control of TR2 by feeding 12v to TR2's base thus turning it on, or grounding TR2's base thus turning it off regardless of what the central locking is feeding into TR1's base.
What this means is, when you unlock the car the central locking has control and opens the mirrors, when you turn on the ignition 12v is fed from the manual switch to TR2 thus taking control of the circuit away from the central locking in this way if the central locking operates over 10mph it will have no effect on the circuit and the mirrors will stay out.
Only when you stop the car and switch the ignition off does the central locking take control again. So when you lock the car the mirrors come in.
When the ignition is on you have full manual control so you can bring the mirrors in manually to park in a narrow garage for instance.
If you want the mirrors controlled by the ignition only then don't fit D4, without D4 there is a low impedance path to the base of TR2, which causes the relay to drop out when the ignition is turned off.
D4 blocks this low impedance path and allows the central locking to keep control of the relay when the ignition is off. So if you want the mirrors controlled by the central locking then D4 is essential.

Originally Posted by hgt

It seems the maplins relay in the parts list is slightly different to the one I used. this is the wiring diagram for the maplins relay

In which case I'm claiming (my!) stupidity rather than just plain lazyness - you lost me at " CIRCUIT DESCRIPTION
The manual switch simply reverses the polarity of the feed to the motors,"