I made this guide years ago, thanks to the guide "blink on niko", although it was a bit hard to understand and had poor quality pics.
First 156s only had blinking lights when locking if it was equipped with alarm from factory, the rest didn't have such feature.
Later models corrected this.
I was pretty sure I had published the guide here, but I couldn't find it anywhere, so it seems I forgot!
For all impatients, this is what you'll get:
YOU'LL NEED THE FOLLOWING
- 5 meters of flexible wire. 1 or 1.5mm section is more than enough.
- 12V relay, double contact,normally open. Also you can use two single contact normally open relays, and wire the coils in parallel (I went this way).
- Soldering iron, about 20cm of thin wire, 0.5 - 0.75mm section
- Different wrenches, screwdrivers... Best to have multimeter too, to verify connections.
First, disconnect battery!!
The circuit is very simple:
Open boot, remove upper cover. Near to the lamp you'll see a small black box. That's the central locking unit, called M35.
As seen in the picture, pin "1" sends the blinking signal. However, there's no cable going anywhere, because only alarm equipped cars had this signal wired.
Get the 5m wire and connect it to the pin 1. You can just peel a bit of it, then slide through the hole and apply some silicone to lock it on place.
I was lucky, I had an old video that had a similar connector, and cable pins fitted well;
Once wired, take the multimeter, set it on diode "beeping" mode, put one tip on ground (any nut, plate that touches the car's body) and touch the wire with the other tip.
Put the battery back, and push the locking on the FOB. It should beep when the lights signal turns on, just like this:
Disconnect battery again.
Take rear seats off. Also remove the plastic covers on the sides, and the driver's belt.
Remove fuse box and pedal covers.
Remove all screws holding it on place, also you'll need to remove some connectors from the fuse/relay box, then take it'll come out. It's a bit hard, everything is very tight.
Once out, pass the wire up to the fuse box.
Start on the side, near the shock absorver, and wire it all over the side, taking care to put it behind the carpet to protect from stomps.
Remove "H" connector, it's this one:
Remove pins 3 and 7, pushing them out with a clip, once out carefully solder or join the slim 0.75mm slim wires, and push the pins back into the connector.
Instead all this, you can simply use wire taps. I didn't had them, so I had to solder.
It should look like this:
Get the relay (or the two single circuit relays), solder the slim wire we joined to the "H" connector to each circuit normally open contact.
Solder the wire we passed from the boot to one side of the relay coil.
Now join the other side of the coil with remain contacts, remember, only the normally open side!
And finally, wire it to 12v permanent. For safety you should put a 10A fuse between (I didn't)
This is how I did:
The white wires are the ones I soldered to the "H" connector.
The brown one is the wire coming from the boot.
The black wire goes to the 12V permanent.
I searched for the permanent supply, I found one source on this connector.
My wire already had a crimped terminal, so I just pushed it in. It got in pretty hard, so I', sure it won't move!
Put the fuse box back, left the relay hanging from the other side.
I wanted the best building quality, so... I gave it 10 turns of insulating tape
Then hide and lock it up with a cable tie.
Now you're ready for the final test! Connect the battery and hit the locking button on the FOB! It works or it burns?
Put all the bits back, and be proud! You've updated the technology of your alfa at the level of a 1991 Wv Polo!