Hello all, I saw several users described already the similar problem but their cases seemed to be different from mine. "Check EV system" is very generic error message.
I have a problem with the car (kia soul EV 2015). When driving in a hot day it can simply turn off and refuse to turn on again with a error message on display "Check EV system". After some time (a few minutes) it turns back on but soon turns off by itself again with the same error message. Two dealerships that I asked to fix the problem failed to do that, so I have to find the root cause on my own.
Having a reasonable assumption that the problem might be hidden in the HV battery cooling system (I will describe in details where this assumption comes from as a second message to the topic) I checked the blower in the trunk. It is the blower which intakes air from the cabin and use it to cool the battery a bit. I was surprised that the blower was not spinning. It was a hot summer day (~30 degrees under the sun) and the cooling fan was not working. I measured the voltage which comes to the blower - it was zero. Fuses are ok.
There are four cables which come to the blower: power, ground, PWM (for controlling the speed) and the fourth for measuring the current speed. So the voltage between power and ground was zero. I think it explains why the fan was not spinning and I had problems with the car during hot days.
However I still have questions for further clarification. Do I understand right that the battery cooling fan should always have power voltage on it? I think that the fans whose speed is controlled by PWM are always powered even when they are not spinning. Otherwise I might have measured the voltage at the time the cooling was not required for the battery (yet it was 30 degrees outside and I had just driven the car).
I also would like to check if the fan is not deflective. I would like to give power voltage to it without any control wires such as PWM. I expect it to spin at its maximum speed in this case. Do you know which power it consumes? I could not find any specifications but I think it is 12V DC.