Okay, so today I got somewhat into the direction of forwards but still some curveballs.
The first thing I did was apply power directly to the instrument cluster (after having removed it) to see if the lights for the instruments, speedo, and such were working. And the good news is they are. Which to be fair I did expect that. So, while the IC was out I tested connectors 0233 & C1280 for continuity across their corresponding pins.
Here's what I have so far found (I hope this shows well);
C1280 C0233
1<--------->3
2<--------->2
3<--------->15
4<--------->none
5<--------->18
6<--------->none
7<--------->none
8<--------->16
9<--------->13
10<------->12
11<------->5
12<------->none
13<------->none
14 <------>8
15<------->10
16<------->9
So as you can see (hopefully) is that they don't all have a corresponding pin on either of these connectors. So what I am trying to find out in RAVE, looking at the schematic, is where those wires that don't match on these two actually go. On C0233, RAVE says pin 6 goes to the interior lights & pin 20 goes to the HEVAC, 4 & 14 are power(I believe they both must come from connector C1276 but I haven't as yet checked that yet. I'm trying to trace them via RAVE and see where they actually connect). 7 & 17 both go to earth/ground, and when I checked continuity with them and the earth point in the drivers RHS footwell it was all good. I don't yet know where wires 1, 6, 11, 18, 19 on connector C0233 go and I also don't know where pins 6, 7, 12 & 13 on C1280 go.
What I do know is that pin 6, the red & white wire on C0233, when checked for continuity with the ground point in the driver's footwell it says it's a closed circuit. Yet RAVE says that should go to the interior lamps. It is all pretty confusing for me but I will soldier on. As I say up until this problem started about a month ago everything was working fine.
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