Hello all , newbie here just trying to learn and find the solution to my problems . I Did a LS swap using a 2002 escalade 6.0 and ECU ,,,using a LS1 stand alone harness. I noticed something was draining my battery and I found that the one red wire going to the alternator and the white tach wire from the harness has power to them at all times , even when the car is switched off . This is what was killing my battery. im pretty sure those wires are not suppose to have power to them at all times. Is there something in the ECU that controls these wires to cut the voltage on and off to these wires ? The harness has only 4 power hook up , 2 wires from the harness go to the starter , having constant power. the other two wires comes from a key on 12volt source to operate the two relays , one controls the ECU and the other controls the fuel pump relay . I can pull the , key on 12 volt power that controls the two relays and I still have voltage going to the red wire going to alternator and the white tach wire. I was leaning toward the harness being wired wrong . I sent the harness back to the company I bought it from . The company, in turn sent me the same harness back saying they had looked it over and it had tested fine. I don't know how they tested the harness but assuming they put it on a test engine and started it up but did not check the voltage when engine was off , it would have tested fine , as my engine runs fine with the harness . So now, im leaning toward the ECU either being bad or something in the programming is keeping those wires energized at all times.
I just ordered the hp tuners MPVI2 yesterday , so I haven't looked into the programming yet, and really don't know what to look for. Any help or advice will greatly be appreciated .
Thanks