350i door mirror wiring

[gas mart 1]

Hi All, can anyone explain the mirror wiring on my 350i, I have got a replacement motor which is the correct size and all bolts line up, but the replacement has only 3 terminals where as the original had 4. Looking at the picture of the replacement, the centre terminal feeds both motors. Does this mean I simply join two wires together ? if so which wires. The wires are black , white , blue , brown .I made up a test light to try and find out which wires , but the bulb seemed to light up which ever combination of colours I tried.
Cheers
Martin

Edited by gas mart 1 on Wednesday 26th October 18:18

[billynobrakes]

Funny been looking at finding the right one myself and you need BMW part number 51161394107 that's the right one, ordered one yesterday and just waiting on delivery, anyway hope that helps

[Wedg1e]

Here's the wiring diagram:

http://www.wedgeneering.co.uk/TVR%20390SE%20p7.htm

I'm struggling to see how any two terminals could be linked and it still work, sorry.

The SAAB 9000 is another car that used the same unit.

[ElvisWedgely]

Here is what I think. You have the wrong motor for this cercuit.The mirror moves in four directions. Up, down, left and right. Looking at the wiring diagram blue and black wires supply power for motion left and right and the white and brown supply motion up and down or visa versa. Therefore in this cercuit you cannot use a three terminal motor. However, if the mirror system was wired in a different way then it would be possible to have the motion in all directions with a three terminal motor. I could be wrong but without being there to do some electrical testing it's hard to say for certain. I would try and get a mirror motor with four terminals to be sure. Just my opinion.

Tony. TCB.

[gas mart 1]

Thanks for all replies , I have now found the BMW 3 series ,4 pole motor, on flea bay , looks identical to the original .
cheers
Martin