Radiator fans Not working properly
 

I've had my 370z for about 8 months and I haven't been able to fix the problem with my radiator fans. They are constantly running on the highest setting regardless of temp. Even in accessory mode, the fans kick on full blast. I've replaced the thermostat (which was faulty), coolant temp sensor, fan control module, ECU (fixed other problems), the radiator fan fuse, PWM relay, and the fan motors themselves. All that is left is the wiring. According to the Nissan dealer, the ECU I provided tested fine. Is there another control module that can be tuned other than the ECU so that the fans stay on all the time? Nissan tech says that my car doesn't let his Nissan diag tool connect due to lack of voltage since the fans are on during accessory mode. Also, there was never any CEL regarding the fans. I also forgot to mention that I replaced the IPDM fuse box. Any ideas? Appreciate the feedback

I have a similar issue after I swapped my transmission in the car followed with the wiring harnesses. When the car is on(no start) the fans spin as fast as they can but the obd port wont connect to the scanner for some odd reason even though I know I plugged everything in properly. My car doesnt start at all. I towed it to Nissan on Monday and haven’t heard from them since Tuesday of this week ever since. If your fan is running after you replaced everything know to man then it has to be wiring. I have voltage but bad grounds. Best bet is to find a shop that specializes in wiring or Zs but if you take it to Nissan they can probably figure it but at a cost. If you want to try to fix it at home try testing the voltage if everything is getting powered because my tuner told me that if the fans spin then its a indication that the ecu is not communicating.