Although we have many thread to discuss the auto dimming mirror, but the information is here and there, and not easy to search at all.
The rain sensor and auto dim mirror are from a 02 vectra. The mirror have 4 PINs(no driver door mirror dimming) and rain sensor have 9 PINs(no daylight sensing).
The pinout of 4pin mirror is like this:
1, Black, +12VOriginally the mirror is connected to the REC like this:
2, Brown, GND
3, Grey, Pulled up at 12V, Connect to ground to cancel auto dimming
4, White/Black, Pulled down to GND, Connect to 12V to cancel auto dimming
PIN4 in the mirror is not used. PIN10 in REC XR8 is used for cancel the dimming when in reverse gear or doors open. This pin must be tech2 to activate.
However, if you don't have tech2, you could:
Connect PIN4 of mirror to reverse lamp (white/black IIRC), and connect PIN3 to PIN12 of XR7. By doing these, the mirror will cancel the dimming when in reverse gear or doors open or interior light on.Rain sensor must be tech2 to activate. It's connected like this:
I have a vauxcom so i use original way to connect the mirror.
Rain Sensor--------REC XR7
PIN3---------------PIN16, Rain signal
Bought a 5m ribbon cable and 2 connector, less than £5.
Re-arrange the connector according to a IDC pinout.
Install the ribbon cable as how2, then make two connectors for auto dimming mirror and rain sensor.
Insert the missing PIN to PIN14, PIN15 and PIN16 of REC XR7, and connected accordly, finally like:
Total cost: £4.8 for ribbon cable and 2 IDC connector (2x5 way), £25 for mirror and rain sensor.
I glue the rain sensor to the windscreen with a kichen silicon glue, works find.
Next task would be to find a rain sensor with light sensing, and modify the light switch to Auto.