davidhayesnz
New member
- Joined
- Nov 9, 2024
- Messages
- 1
I'm new to this group. Thanks so much for all the great information I have found already.
I have two MIEVs
Car A. This had a few problems including the air conditioner didn't work, air bag issues and some more. However it had a good 10.5KW battery, charged and drove just fine.
I then purchased another;
Car B with a 16Kw battery that had problems charging including it stopped charging when showing at about 60% charged and it wouldn't charge from a granny charger but it would sometimes charge with a 16amp slow charger. The battery status on the dash would also go blank at random times and then the car would not drive though it would recover from this after a variable amount of time. Otherwise the car was in in very good condition. It alos wouldnt consistently charge on a fast charger . It would keep stopping and would go about about 60% as shown on the dash.
So ....
I swapped the 10.5 Kw battery and BMU into Car B from Car A. Perhaps I was lucky doing this but Car B now with the 10.5KW battery has no issues at all so I have ended up with one very good car.
I then tried putting the 16Kw battery and BMU into Car A but it has the following issues.
Battery wont charge at all
ODB readings show all cells at either 4.01 or 4 volts. I think that means the battery is actually fully charged right? even though its showing at about 60% charged on the dash
Car wont go to ready but with turn on and has the fault light on. The lead battery will then slowly drain as the only power being supplied in the car. For a while after the 16Kw traction battery was installed the car would go to ready for about a second and then go back to not ready. That no longer happens. It just doesn't go to ready at all.
My thoughts
Good readings on all cells suggests the battery cells are OK?
At least one problem must be in the battery pack cells or the CMUs or the BMU (from under the back seat) from Car B as these were the only things swapped between cars.
So excluding the possibility of new issues the onboard charger and motor controller wiring and lead battery should be fine. - They were all working fine before the good battery was swapped out of Car A to Car B. I have tried another good small battery with no change in the problems
I have removed the traction battery and all battery packs measure at about 32volts. So this matches with ODB reading of 4 or 4.01 volts for each battery cells
Thoughts on this please. Should I try getting a replacement BMU and see what that does or is it also very possible that some of the CMUs are the problem. How might I narrow down where the problem is? Otherwise I may just keep the car for parts and breakdown the battery for use in other applications but curious to see if I can resolve this.
Many thanks for any ideas
I have two MIEVs
Car A. This had a few problems including the air conditioner didn't work, air bag issues and some more. However it had a good 10.5KW battery, charged and drove just fine.
I then purchased another;
Car B with a 16Kw battery that had problems charging including it stopped charging when showing at about 60% charged and it wouldn't charge from a granny charger but it would sometimes charge with a 16amp slow charger. The battery status on the dash would also go blank at random times and then the car would not drive though it would recover from this after a variable amount of time. Otherwise the car was in in very good condition. It alos wouldnt consistently charge on a fast charger . It would keep stopping and would go about about 60% as shown on the dash.
So ....
I swapped the 10.5 Kw battery and BMU into Car B from Car A. Perhaps I was lucky doing this but Car B now with the 10.5KW battery has no issues at all so I have ended up with one very good car.
I then tried putting the 16Kw battery and BMU into Car A but it has the following issues.
Battery wont charge at all
ODB readings show all cells at either 4.01 or 4 volts. I think that means the battery is actually fully charged right? even though its showing at about 60% charged on the dash
Car wont go to ready but with turn on and has the fault light on. The lead battery will then slowly drain as the only power being supplied in the car. For a while after the 16Kw traction battery was installed the car would go to ready for about a second and then go back to not ready. That no longer happens. It just doesn't go to ready at all.
My thoughts
Good readings on all cells suggests the battery cells are OK?
At least one problem must be in the battery pack cells or the CMUs or the BMU (from under the back seat) from Car B as these were the only things swapped between cars.
So excluding the possibility of new issues the onboard charger and motor controller wiring and lead battery should be fine. - They were all working fine before the good battery was swapped out of Car A to Car B. I have tried another good small battery with no change in the problems
I have removed the traction battery and all battery packs measure at about 32volts. So this matches with ODB reading of 4 or 4.01 volts for each battery cells
Thoughts on this please. Should I try getting a replacement BMU and see what that does or is it also very possible that some of the CMUs are the problem. How might I narrow down where the problem is? Otherwise I may just keep the car for parts and breakdown the battery for use in other applications but curious to see if I can resolve this.
Many thanks for any ideas
