E39 communication issue

[andreisoar3]

Hi everyone,
I m troubleshooting a diagnostic communication on my bmw e39 520i from 2000( i have the 20 pin port in the engine area and also the 16 pin obd in interior ),my diagnose interface is latest ICOM(genuine) and 20 pin adaptor to obd.. i need some expert advice-here s the situation:
symptoms and issues:
- no communication with most modules except an error on cylinder 6 found on INPA ( so i think it s communicating with dme) -did that on 20 pin and obd -same result
-INPA shows me ignition off and ista reports kl15:0 ,even though ignition is on!!
-measured voltage on pin 7 inside interior obd 2 and shows 10.5v instead of 12.
- i tried different 20pin adaptors but nothing. also verified x183 connector and it s in perfect condition, no water infiltrations. i also bridged pin 17 and 20 from 20 pin port.
had a problem for 1 year or so with an airbag light on the cluster - so now i disconnected the mrs ( airbag module) but the problem persists ( once i removed the mrs the airbag error/light dissapeared from the cluster! but i still cannot communicate with the modules). also i checked inside the mrs module and it s in perfect condition,no water damage ..
- i also checked some fuses in the glovebox area and they were fine.
CLUSTER seems to be a key suspect since all major bus communication pass through it. Also the cluster shows for the past 2 months ABS/ASC error ( maybe it s a abs sensor maybe not..)
i suspect the cluster might be corrupt or defective blocking the k line signal to the obd port

questions
-is the k line ( pin 1 white connector ) in the cluster directly responsible for passing communication to obd pin 7?
-if i bypass the cluster and run a direct wire from k line ( white connector pin1) to obd pin 7 ,should i regain diagnostic access?
-could a faulty cluster cause all these errors?(abs ,asc ,airbag) and block the k line communication?
-is 10,5 volts on pin 7 from interior obd a sign of a short in the cluster ?
-can i use xprog or r270 to read /repair eeprom corruption in the cluster or in the mrs if needed?
-could the ignition switch be falling and not providing 12v to kl15 causing communication issues ?

ps: i don t have any ignition swith problems except my key if it s related to it. well the key works remotely whenever it wants..a month yes,a month no . i saw that when it s rainning or i do wash the car it starts to work for a period of time. the programming key method does not work for me.. - talking about the method by switching on the ignition and off and hold lock while pressing unlock 3 times.the key battery is good

Any recommendations would be greatly appreciated! thx in advance