Hi all, long time Prius fan and recent owner of a Prius C to replace my aging first gen Honda Insight. Familiar to an extent with the Prius system as I've gotten my family into the Prius gang for about 5 years now. I remember reading a while back about a mod for the Gen 2 Prius where you could set the hybrid battery cooling fan to run at max speed to keep the battery cool. Does anyone know if a mod exists for the Prius C, and if so where it is documented? Spent a good amount of time trying to search for it, but it either doesn't seem to exist or my searching skills need improvement.
I don't know about a mod- there may have been one in the past? Lately everyone talks about using an Android app with an interface cable to send override commands to the fan controller to keep it at full speed. Seems to be how its done now.
There is a member that has a signature link with a description of the link something like Keep you battery cool set your battery fan to full speed" I'm not a fan of keeping the traction pack fan at full speed all the time, because it can hide traction pack issues that should be addressed sooner than later with the traction battery pack temperature. The DrPrius app Hybrid battery diagnostic and repair tool for Toyota and Lexus has a feature to set a battery temperature where the fan will start. It's described 2:50 time mark in this video
Typically in older hybrids the heat in the packs are due in part to the imbalance between modules. The higher the the voltage difference between cells / modules, the higher the temps in the pack, especially the modules in the middle of the pack.... Unless one lives where temps are always above 90 F I wouldn't want my battery fan set to high all the time. It's always a good idea to make sure air is flowing from the cabin threw to the battery too. It doesn't matter how slow or fast the fan is running if no air is getting to where it's supposed to go.
Attached Torque Pro PID file for the fan controls. Edit file extention from .txt to .csv and import through app settings