2004 prius Runs great after I did all the maintenance. Plugs, atf, coolant flow control sensor, oil, filter, cleaned tb, new coolant, inverter pump is fine. Vsc and ! And red triangle are on Only code is vsc 51 aka C1310 Any advise would help. I'm a retired master mechanic and would prefer to figure out the source of my problem myself. More info is that the vehicle was in a front end collision. What I notice is during the first 5 minutes of driving, the brake regen doesn't work when I let off the gas pedal. The display screen still shows energy going towards the wheels instead of the green regen going back into the battery. It only does this for a few minutes. It will work if i step on the brake pedal though. I think it has to do with the vsc being pulled back to limp mode or something to that nature. I've tried doing the 8 pump brake technique with no avail in order to reset the code but it didn't work. Also the driver's side fan kicks on all the time. Usually at start up and stays on all the time.
I've been doing my research for a week before I was forced to post the thread. Can't find anything with more in depth detail concerning the vsc 51 c1310
Morgan- what diagnostic tool are you using? I would start by getting a mini VCI cable for a deeper diagnosis as c1310 is not very specific. The mini VCI may pick up more detailed information needed to understand what is happening with HV system. My guess is that its the ECU. Jessica
The HV battery fan is located in the rear on the passenger side. Not sure if this is what you are hearing... Typically a symptom of HV battery overheating.
Did the warning lights turn on after the front-end collision, and prior to your performing maintenance? In other words, does accident damage still exist that was not properly repaired? DTC C1310 is logged by the skid control ECU and this means that ECU is aware of a problem with the hybrid system. I agree that you will need Mini VCI running on an Windows XP or Windows 7, 32 bit OS laptop so that you can find out what additional DTC have been logged. Further, you can subscribe to techinfo.toyota.com to obtain factory repair manual info once you have determined what other DTC exist. Good luck.
It's the driver's side radiator fan I'm working on a friends prius who is not that mechanically inclined. I did all the maintenance before I had to leave Washington. Cars drives great besides the vsc light. Won't be able to get back to it for another 2 weeks so I'll keep you informed.