Although this happened on my 2012 Prius-C, I put it in the Prius forum because it probably applies to Prius too, and there are more Prius owners than Prius-C owners. After running in maintenance mode for about 30 minutes, the traction battery SOC level dropped from 6 to 2 bars. Is this normal? Isn't the traction battery charged in maintenance mode? With forced charge (drive+brake+gas), the SOC level bar goes up nonlinearly. It takes about 1 minute to reach 3 bars from 2 bars, but about 3 minutes to reach 6 bars from 5 bars. It seems to stop at 6 bars and will not move up any more. Again is this normal?
Regarding the maintenance mode question, I am not 100% certain, but if I remember correctly I have read that is the case (thus the warning not to drive the car in maintenance mode). Additionally, I witnessed the same thing when I put mine in maintenance mode. Regarding the limitations on how full the battery gets when force charging occurs, the system is limiting it due to rising battery temperatures anticipating battery damage and preventing it from occurring.
AFAIK, maintenance mode is primarily used to keep the ICE running so a mechanic can check its function. I would think that "normal" HV control limits would apply- hybrid ecu lets it get down to 1-2 bars then charges it slightly to keep it around that level, but no more. Posted via the PriusChat mobile app.
