Soul 2015 - Check EV system (error) / battery cooling failure?

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.

Why I think it's the battery overheating:
The problem occurs on hot days only (sunny summer days). The error goes away after some idling (natural cooling - even chilling)))).
With the fact above I think it's definitely overheating. However it might be either engine either battery.

Second fact. The error might occur on mild summer days (cloudy weather with 15-20 C degrees outside) if the car has been charging prior to driving. In other words if I disconnect the car from an outlet (1 level I use at my place) while it is charging then the error might occur even in milder weather conditions. Given that during the charging the engine does not heat up (at least I think so, please correct if I am wrong) the battery rests the only candidate for experiencing problems.

spirit said:

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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.

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It seems likely, as the service manual requires the auxiliary battery to be disconnected to remove the fan. See https://www.ksoulev.com/cooling_fan_repair_procedures-3013.html You may get more clues in the manual, but it is not very impressive in my view.

I strongly recommend using something like Soul Spy on an Android phone with a Bluetooth OBD-II dongle to look at what the battery is doing in terms of temperatures and whether it thinks the fan should be on.

IanL said:

spirit said:

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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.

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It seems likely, as the service manual requires the auxiliary battery to be disconnected to remove the fan. See https://www.ksoulev.com/cooling_fan_repair_procedures-3013.html You may get more clues in the manual, but it is not very impressive in my view.

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Hello IanL. The described test procedure might help me with diagnostic btw. However the software looks fancy. Is it accessible only for the dealerships? What does it mean "Connect the GDS to DLC?

notfred said:

I strongly recommend using something like Soul Spy on an Android phone with a Bluetooth OBD-II dongle to look at what the battery is doing in terms of temperatures and whether it thinks the fan should be on.

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Hello notfred. Oh yeah, I thought about this kind of monitoring. Can you suggest a device which can show the required data? There are plenty of products on the market whose price varies from 20$ to 200+$. A hard choice(((.

https://evranger.com/en/soul-ev-spy-users-guide.html

Q: Which dongles does the Soul EV Spy app work with?
Only Konnwei KW-902 ELM327 v 1.5 is supported.The app does not work with ELM327 v2.1
dongles, Some testers have reported partial / intermittent data with other ELM327 v1.5 clones, but
they are unsupported, so you cannot expect the app to work with those.

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spirit said:

What does it mean "Connect the GDS to DLC?

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I think the GDS is a PC running proprietary KIA/Hyundai software. The DS probably stands for Diagnostic System.

The DLC is the OBD2 port in the car - the Diagnostic Link Connector.

I made use of kia soul spy software - it's cool and works with a torque I borrowed from my neighbor (not recommended one). This week is said to be cold - a lot of rains so perhaps it will take more time for further debugging. However thanks to the app I can already object one of my previous statements: during the charging process the engine is heated considerably whereas the battery don't get heat up. So the root cause of my problem might also be the engine.

I think I am closer to the root issue now. Again, thanks to notfred for pointing out the awesome kia soul spy app. The problem is not the HV battery overheating. I think that motor overheating is more likely.

Today I was testing the car and I was able to heat the engine up to 100C degrees. I think it was 103 actually. I opened the hood and looked under it. The radiator fan was not spinning. The coolant pump was working however it was working at low pace. I assume that the intensity of the coolant pump is adjustable and depends on the motor temperature.
I went back to the garage, switched off the car and plugged it in to my level 1 charger. The engine coolant mechanism ignited at the full capacity. I noticed how the coolant pump started first slowly at the same pace as it was working when driving. But eventually it accelerated considerably. Soon the radiator fan turned on. So at this point I understood that the radiator fan switch on/off depends on the coolant liquid temperature in the radiator (like in good old cars). So I am not sure what the flag "vmcu.radiator_fan_request_of_motor" in the kia soul spy app for.
I disconnected the car from the charger and ignited it - the coolant pump was very slow again. I switched off the car and plugged in the charger back - coolant pump worked at its maximum capacity. This time the radiator fan did not turn on - perhaps because by this point it was not hot enough.
Do you guys have ideas what to do next? To me it looks like the coolant pump is not well controlled when the car is in drive mode.

I wish I could be of more help here, but are you sure it's the motor that's getting hot? Perhaps there's been a mistranslation?

The only thing I could see getting hot besides the battery during/after charging would be the inverter. Which, interestingly enough, is known to have issues in the early model year, as far as I understand.

EVDee said:

I wish I could be of more help here, but are you sure it's the motor that's getting hot? Perhaps there's been a mistranslation?

The only thing I could see getting hot besides the battery during/after charging would be the inverter. Which, interestingly enough, is known to have issues in the early model year, as far as I understand.

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Hello. I checked it with the kias soul ev spy application and the temperature parameter which got high is vmcu.motor_temperature. I think it's the engine. Maybe it's general name for nodes in the same block? However I cannot be 100% sure. There were also other temperature parameters: mcu and mcu_heat_sink. But they were in normal.

Hello guys. I am really concerned about the EWP ( water pump) behavior.
Do you have any information why it might work at different speed when powered from battery and from ac charger?
Maybe If you could check it on your car and confirm or object such behavior? I would appreciate it. Because I am not aware if it's a bug or w feature. Thank you in advance.

Today is a hot day outside so I was able to "break down" my car again. In terms of temperatures I see that it is defenatly not battery nor engine. Battery was 30 C degrees ( as usual), the motor was 50 C. It used withstand temperatures more than 70 so it is something else.
All others nodes I was able to trace: motor CPU, on board charger and ldc aux battery charger were all about 50 degrees. It looks like they all got the same temperature so I am not sure which one of those causes failures.
Do you know which one of them has shut down threshold?
Is there any other nice which can be overheated and whose temperature is not traced by soul ev spy?

If all those things are the same temperature then that suggests that the cooling system is working properly with the EWP circulating the coolant through them, otherwise some would be hotter than others.

If you use something like the "Torque" app, are there any codes registered?

Is there anything showing up on the battery cooling fan? Does that definitely work?

notfred said:

If you use something like the "Torque" app, are there any codes registered?

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Yes, there is a fault code P0A42. The same code is shown by the spy app as well: OBD.DtcCodes.7EA: [P0A42]. The explanation I found on the Internet is: "Drive Motor A Position Sensor Circuit High" & "End of Range – Circuit Higher Than Expected". Not very verbose to me.

notfred said:

Is there anything showing up on the battery cooling fan? Does that definitely work?

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battery_fan_status: FAN_STOP. It is always stop and I don't know when/if it should move to other status. Also the voltage coming to the fan is zero (I mentioned it in one of my first messages) which is strange. I think it should be powered even if it is stopped. For example I measured the voltage for EWP. It was 14V even thought it was not spinning. So the battery cooling system was my first guess.

I think the fault code is pointing to your problem.

The motor is a 3 phase AC motor, so the motor controller needs to know the exact position of the shaft at all times to know what phase to apply to the coils to make the shaft turn at the right speed. It has 4 signals coming from the position sensor to help work this out. What it is saying is that the first signal is always high - i.e. shorted to positive. This could be a problem in the connectors or wiring to the sensor, a problem in the sensor itself, or a problem in the motor controller.

Given the way you have the problem when things are hotter, I suspect this is just be an intermittent problem - either the sensor or the circuit driving it is going bad and just fails when hot, or as things warm up then the wire and connector are having problems. If the sensor is giving bad data then the motor will not be getting the current at the right time and it can cause it to heat up more as well, this would match with what you see with high motor temperatures.

Unfortunately the service manual doesn't really give any info on the position sensor itself, just the wire to it and the connector. I would post the link to it on https://www.ksoulev.com/kia_soul_ev_ps_ev_2015_2020_service_manual-2239.html but unfortunately that site is missing the last 3 sections of the manual, including the section on the traction motor. If you can find a link to the PDF, it's pages 1336-1338, it does give the test resistance measurements.

Looking at the parts list on some online stores, they also doesn't show the sensor, just the motor as a whole, so I'm not sure that you can replace just the sensor. Anyway if you did then you need to do the "Initialization of Automatic Resolver Offset Calibration" which is going to require the Kia GDS that the dealers have.

I would suggest very carefully checking the wiring to that sensor (Danger! NOT the High Voltage motor wiring!!!) and the sensor resistance readings, and hopefully it's just a bad wire. If the wire is OK and the sensor itself is bad then a new motor is very expensive (probably more than $5000 US). If you can find one in a junk yard (unlikely), I might see if undoing the bolt holding the sensor connector brought the whole sensor out that I could then replace on my car and take it to the dealers for the calibration, but I wouldn't try undoing that bolt on my own car first in case it snaps wires inside as it comes out, or at least lets all the coolant out. Also if it is the motor controller that is bad then it is a similar cost and I don't know of anyone doing EPCU repairs.

Thank you Notfred for the explanation. What you described does not look very positive. I can verify the wires and the connectors but not further. Also bad wires might not have a visible defect which complicates the staff a little bit more.

I think that if the engine is to be replaced it should be covered by the warranty. I still have some time. 8 years of warranty (the vehicle is of 2015) for the HV battery and the engine. However the dealerships kind of refuse to acknowledge the problem. I went to them twice with this issue, they did something (meanwhile charging me 130$/hour + tx) and this "something" apparently has no effect. The last time they even told me that the car had no fault codes whereas I knew that the car was showing the error code (the same code related to the motor sensor position A) because I had checked it before. Can you suggest a way to speak with them? Thank you again. I appreciate your attention and you wish to help.

I doubt you will get much from the dealer - they simply lack the expertise to tackle the problem and try to make it go away. I think you should contact KIA, tell them everything in as much detail as possible, and hope that they either lean on the dealer, or, better still, support the dealer with some expertise.