Nissan has some pretty crafty ways of laying out the circuitry in their vehicles,they are very sensitive to grounding issues and some of the grounds control multiple modules inside the car, it is very easy to overlook this when grounding multiple items into an existing ground location and it can result in some serious ECU ECM issues although the vehicle may still run and drive fine. To be safe I would undo everything you have done and see if that corrects the issue,if so consider taking your equipment to a shop that does the installs every day (you may already know what your doing Im not trying to be mean or anything) that way if something goes wrong you have someone to be held accountable, those Nisssan computer modules are extremely expensive. Good Luck.