MG5 won't balance charge (2020 pfl exclusive)

[MickeySw]

My module voltage at 100 percent soc is around 3.27 v according to g to carscanner

Something wrong here, for a MG5 (NMC) it should be over 4V/cell @100% SoC

 

[Pebblefeline]

Someone with more knowledge will have to explain this as everything is normal and my range is good.

Main hi voltage pack shows 403 - 405 v fully charged

 

[Coulomb]

My module voltage at 100 percent soc is around 3.27V according to Car Scanner.

Unfortunately, that makes no sense for either chemistry.

For LFP, it should be around 3.65V per cell, though it may relax from there to some 3.5 VPC over several minutes after charging.
For NMC, it should be around 4.21V per cell.

Are you using a vehicle type that suits your actual vehicle? The app has to know the exact vehicle type in order to interpret the CAN bus data correctly.

 

[DaveM]

Sorry if I sound an idiot. But this is all new to me. How do I go about checking, that it is balancing, what do I look for, my PFL MG5 is working fine, but after a full charge I get a figure of 173 miles. Is that normal , what do I need to do to check it.
Thanks.

 

[MickeySw]

Sorry if I sound an idiot. But this is all new to me. How do I go about checking, that it is balancing, what do I look for, my PFL MG5 is working fine, but after a full charge I get a figure of 173 miles. Is that normal , what do I need to do to check it.
Thanks.

No need to worry, balancing isn’t affecting range (unless it’s way off and then the car would throw a fault). What year is it and what’s on the clock?

Btw, when you see 173 miles, did you reset all trip logs beforehand?

 

[Alb]

Unfortunately, that makes no sense for either chemistry.

For LFP, it should be around 3.65V per cell, though it may relax from there to some 3.5 VPC over several minutes after charging.
For NMC, it should be around 4.21V per cell.

Are you using a vehicle type that suits your actual vehicle? The app has to know the exact vehicle type in order to interpret the CAN bus data correctly.

For info, I just did a snapshot of my Mk1 (NMC) at 100% indicated SOC:

 

[MickeySw]

For info, I just did a snapshot of my Mk1 (NMC) at 100% indicated SOC:

Yes, that’s what I would expect, except SoH 100% for a PFL, @ what mileage?

 

[Alb]

Mileage is 12,368.

 

[Pebblefeline]

Hmmmm using the mg 5 profile in car scanner.
The min max overall is 4.2 ish V.

The individual modules read out as I posted
No idea what this means.

 

[Petriix]

Lol, sorry, I think it must've been 4.22/4.21V.
Edit: no, they're definitely 3.22/3.21V

 

[Pebblefeline]

The modules that are reading at the lower voltage are labeled CMU01 - CMU24

The main min max voltage is as expected, are these then individual module voltages?

 

[MickeySw]

The modules that are reading at the lower voltage are labeled CMU01 - CMU24

The main min max voltage is as expected, are these then individual module voltages?

Only type 2 battery (LFP) has 24 modules, looks like car scanner is set to the wrong profile?

 

[DaveM]

No need to worry, balancing isn’t affecting range (unless it’s way off and then the car would throw a fault). What year is it and what’s on the clock?

Btw, when you see 173 miles, did you reset all trip logs beforehand?

Thanks for the reply, mines 2021 30k on the clock. When I had its first MOT and service the SOC was 97. Have not reset trip logs, never touched them. Should I?

 

[Pebblefeline]

Only type 2 battery (LFP) has 24 modules, looks like car scanner is set to the wrong profile?

Set to MG5 profile.
It turns out they aren’t modules, they are the Cell Monitoring Units that govern groups of cells.
I believe the long range has 96 cells so in groups of 4 with a CMU in each? Giving 24 CMUs?
These re reported by car scanner and each CMU reports in the cell voltage to the BMS I think.

Can anyone else with car scanner look at their CMU readings?

Now we are so far beyond my knowledge, I started reading a CMU research paper and ……. Well I got a headache.

 

[Gomev]

Thanks for the reply, mines 2021 30k on the clock. When I had its first MOT and service the SOC was 97. Have not reset trip logs, never touched them. Should I?

Resetting the Accumulated trip resets the GOM to factory WLTP levels, otherwise it's showing a range based on your recent driving, temperature etc. i.e more realistic but less satisfying (unless it is greater than WLTP in summer)

 

[MickeySw]

Set to mg5 profile

NMC cars have 6 modules with 16 cells
LFP use 24 modules with 5 cells.

Each module has it’s own CMU (Cell management unit)

 

[Pebblefeline]

Hmmmmmm so set to MG5 EV on Car Scanner. I am seeing 24 CMUs.

I have tried other profiles just in case but it’s definitely the profile marked MG5 EV.

 

[MickeySw]

Hmmmmmm so set to mg5 Ev on car scanner I am seeing 24 CMU

I have tried other profiles just in case but it’s definitely the profile marked mg5 Ev

Is this the paid (Pro) version?

 

[Pebblefeline]

Yes in the most recent version

 

[MickeySw]

Yes in the most recent version

You might try the ‘native’ model Roewe i5?