This 2005 Suzuki Reno came in with a complaint of a harsh transmission shift and the check engine light was on. I checked codes and there was one stored for the transmission but I cannot remember exactly what it was right now. I think it was P0700, no communication between the TCM and the ECM. Anyways I knew this car had been at another shop and they were trying to locate a drain on the electrical system. That will be another post. I really did not want to do the transmission diagnostics. I detest working with transmission fluid but, after looking at a wiring diagram, I decided to check the basics. The fuse box legend shows the TCM fuse to be three up from the bottom and in the middle of that row.
There was no fuse so I simply installed a new fuse, cleared the code and test drove the vehicle. All was fine. Thank goodness I did not have to do much on this problem.