Door light / contacts thingy

When I open the passenger door the car doesn't realise its open, the door light doesn't come on or the interior light, and I don't get the "door open" message. I've tried cleaning the contact where the wires go into the door and sprayed the contacts also, but it still doesn't do anything. The electric windows and door lock still all work fine, any ideas??? plz

Does it work properly with the engine on? Weird I know but give it try, if it does then the passenger door node is playing about. Disconnect the battery for an hour or so then reconnect and try again

No it doesn't, I've heard about disconnecting the battery and I tried that before, but it still makes no difference.

Ok we are talking FRONT passenger door here aren't we and you haven't got one of those stylish 5 door versions?

So your problem is in the door and is still most likely to be the door to A frame connector as it's quite exposed

This is the area you to want to look at
D30 is the door to A frame connector
N50 is the door switch which is part of the door lock
M66 is the door node

So from the body computer up top -pin 8 the cable (black and white on both sides of the connector or so it says) goes through the connector D30 to the door switch N50, then on through the door node then it goes back back to the D30 connector again and then on to earth at C20
Still with me?

OK so what I would do is go for the easier stuff and see if it works by manually taking the circuit to earth. This will tell you which side of the D30 connector is causing the problem and save a lot of work

So here it is pin 3 at D30 so I would just try connecting the pin 3 on the A frame side (not the door side) to earth. Then with ignition on the wonderfully intelligent system should tell you the door is open and the interior light should light. If it does or doesnt then you know which side to go hunting for poor connections
But which is pin 3?
OK this is where the Fiat wiring guys get all confused talking about passenger side and driver's side but that will depend whether the car is lh or rh drive. But, luckily it's pin 3 on both sides

Here's the connector D30, notice the pins are not symmetrical so it shouldn't be hard to spot pin 3 from the pattern of the pins. Connect that-A frame side- to a suitable earth and see if the magic works

Wiring diag says wire is black/white on driver's side and light blue and green on passenger side but always disbelieve the wiring diags as they like to get their own back for Mussolini

If it does then next port of call is to find out if the earth line is intact and the same connector Pin 27- check that goes straight to earth- zero resistance- properly

OR
Just buy a torch and check your doors are shut before you drive off