So I have a 2000 golf 4 gti , no obd scanners work on the car, even an original rosstech cable won't work . I've done some research and saw that the voltage shouldn't be above 9v between pins 4 and 7 on the obd port ,if so there's an issue with the k line after getting an aftermarket radio installed , my problem is tjsg the previous owner made a mess of the wiring, and I've noticed that the k lines are all spliced into each other , there's 4 grey and white wires joined together, none of them go into the head unit, do I cut these 4 ?