Hell you fine members of the Rover World! So this being my third Discovery 2 went in to check a code and found previous owner had spliced into the ECU connections for Bank 2 sensor 1. The new o2 signal/o2 ground/ and heater signal had been pulled out of original harness. Went in and installed a new extended harness and was still having some signal issues. I checked continuity and low and behold it was OL So i spliced in new wires and while checking my live data feed for signal volts and unplugging and replugging in my ecu several times my OBD2 Port has stopped establishing a connection. Here we go down a rabbit hole of wiring madness. Checked voltage on pin 16 from the port plug and received proper battery power now this is where it gets a little funky. Checked pin 7 and got battery power as wel.l but still no connection for my scanner, and yes I tried the scanner on some cars at work and it was working fine. Now I followed by checking continuity from pin 16 to the header joint, all wires check out to be savy from that point. I hooked everything back up and cranked over then back probed the header and got low/bad voltage from DCU-Airbag, ECU Cruise Control, and ECU-Active Cornering Enhancement, I also had bad voltage from BCU. My question is if I can remove these first three pins and see if it clears up my BCU feed? Im pretty stumped at this point, don't seem to have a ACE ECU or at least I cant find it otherwise I would just connect them. I have the workshop manual but it doesent give me the pin layout of voltages for the BCU. Any input would be greatly appreciated.

 

I could probably narrow this down if I new where the Airbag/Cruise Control/ACE K-line wires went to

 

See if you can find the D2 Electrical Library. That might provide you with some more detailed info about the voltages and pin-specific data.

 

So I’m at a complete loss now, purchased a used ecu/bcu/cluster and still no connection was able to be established. I have disconnected all ecus even though they have 12 volts from the header still with no luck. I feel like I’ve checked everything numerous times and there has got to be something I’m missing here. I’ve been searching high and low for any more information in regards to the matter. Do I need to physically disconnect each ecu or does the header suffice? I checked voltage with the scanner plugged in attempting to connect and no voltage swings to grounds and power.