Question over OBD data

[ianrobo]

Hi,

First time poster, had my MG4 Trophy ER as a company car from Feb and just adore it, best car I have ever had, previous 8 years had two leases for Kia Niro Hybrid.

So in January planning a trip from Birmingham to Berlin to watch snooker ! Got ABRP and the route, using Ionity passport and all great. I trust the car because did a ride to lands End and back in one Day with no issues at all.

So final thing was got an OBD dongle to tie in with ABRP and all data looks fine except one SoC, car shows 80% at the moment but OBD shows 73% and thats been pretty consistent the past few days.

The dongle is a Veepack one and seen no one else with the same problem.

any thoughts ?

Cheers,
Ian

 

[Coulomb]

This is a Frequently Asked Question. There are two SoC values, the "real" one, and the "display" one. The display SoC is adjusted to show 0-100% for empty to full, whereas the real SoC might be say. 0.5-93.2%. (Those are the figures for my ZS EV Mark 1). The Battery Management System prevents use of the top and bottom few percent to increase the expected life of the battery. These "never use" areas are called buffers. So usually, there is a few percent difference between the two SoC figures. For my ZS, 85% displayed is about 80% real, a difference of 5%. The MG4 could well be different, causing the 7% difference that you see. The difference varies with the SoCs; there is probably a value where they agree (difference is zero).

Often there is a way to see both SoC values.

 

[siteguru]

I vaguely recall reading here (in another thread) that the above is correct, and in the MG4 the "tipping point" is about 50% SoC.

 

[fnegroni]

Why don’t you install Car Scanner and tell us the several SoC values in there?

 

[ianrobo]

Why don’t you install Car Scanner and tell us the several SoC values in there?

I did and the values are from there, here is an example from a couple of days ago and when I watch others use this I never see this kind oif difference ? I get of course that the car could be reporting all the battery including reserve and that OBD just reports on usable but that seems kind of wrong ?

 

[fnegroni]

I did and the values are from there, here is an example from a couple of days ago and when I watch others use this I never see this kind oif difference ? I get of course that the car could be reporting all the battery including reserve and that OBD just reports on usable but that seems kind of wrong ?

Some of your values might be incorrect because you didn't change a setting (which I have pointed out to others in other threads)

Also the page you are showing is a dashboard with a custom sensor name, what you really need to do is show us the sensor readings from the "All sensors" page, where the names are as per original configuration.

There are three sensors for SoC, not just two.
State of charge
SoC Displayed
Hybrid/EV battery pack remaining charge

I use the one I highlighted above which is closer to what is displayed on the screen.

This is the setting to change to get correct values reported at all times from all sensors:
Go to Settings > Adapter > Advanced Settings > ELM327 send ATST = Send FF

 

[ianrobo]

Some of your values might be incorrect because you didn't change a setting (which I have pointed out to others in other threads)

Also the page you are showing is a dashboard with a custom sensor name, what you really need to do is show us the sensor readings from the "All sensors" page, where the names are as per original configuration.

There are three sensors for SoC, not just two.
State of charge
SoC Displayed
Hybrid/EV battery pack remaining charge

I use the one I highlighted above which is closer to what is displayed on the screen.

This is the setting to change to get correct values reported at all times from all sensors:
Go to Settings > Adapter > Advanced Settings > ELM327 send ATST = Send FF

thanks a lot I did search through for this and appreciate your patience. Will check it out.

 

[ianrobo]

All sorted thanks !!

 

[HazardLights]

Settings > Adapter > Advanced Settings > ELM327 send ATST = Send FF

I don't have that in Car Scanner settings. Any idea why?

 

[fnegroni]

Settings > Adapter > Advanced Settings > ELM327 send ATST = Send FF

I don't have that in Car Scanner settings. Any idea why?

I’ll post screenshots:

 

[HazardLights]

I am on Use Custom. I assume the set up process for my device defaulted to that and looking closer at the custom initialization string I can see that ATSTFF is being sent so problem solved.