interesting ... 2004-up EPA mandated SAE J2534 pass-through reprogramming from model year 2004
Nissan provides the flash files at
https://www.nissan-techinfo.com* J2534-1 Re/Programming. The NERS software ($350) supports reprogrammable Engine and Transmission control units from 1999 to 2019 model year vehicles.
* J2534-1 pass through device ($39 to $2,700 on Amazon)
* The ECU files are $30 from Nissan. Example:
B15_02_03MY_QR25_5M/T_NAM_ASCD_W/ONATS
* B15 Nissan Sunny/Sentra
* 02_03MY model years 2002-2003
* QR25 QR25DE engine
* 5M/T 5-speed manual transmission
* NAM ?North America?
* ASCD Automatic Speed Control Device
* W/ONATS without NATS (Nissan Anti-Theft System)
Still trying to figure out if mine is the A/T or the M/T ECM. Maybe it doesn't matter -- maybe you can flash a different image to re-program
Is there alternative software besides NERS?