ZS EV LR Will suddenly not fast charge

Chris Law

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Loulé Portugal
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ZS EV
My ZS is almost 2 years old. During a 2000 km trip from France to Portugal, over 4 days, the car initially performed normally at CCS chargers, charging at up to 62kW. After a charge on day 3 at a BP Pulse Iberdrola charger, the Bluetooth stopped working (Wired and dongle). At the next charge and all subsequent charges, the rate did not go above 25kW. I used various providers (Tesla, BP Iberdrola, Ionity, Endesa). I considered disconnecting the 12V battery but decided against it until we reached home. After reaching home I did this and the BT problem was solved. However, charging has stayed in the 20skW. Has anyone experience with this or tips? I have contacted the dealer but will not get a response today.
 
2 things i can think of.

1. 2000 km in 4 days, all on CCS, could make the car derate the charging due to repeated CCS charges, which can be harder on the battery, the car will derate the charge speed to protect the batteries (Well to make sure they dont go below the warranty limit, to prevent them from having to give you a new battery)

2. Loads of CCS charges = Loads of "to 80%" charges = Batteries have not been balanced. If the battery balance between cells gets to high, it might limit the current to protect the batteries.

First thing to do is....Try sticking it on a wall/home/destination AC "Charger" and set the limit to 100% and leave the car to charge until it stops and says it has finished. Then drive it and when it needs a charge, try to stick it on a CCS, if it was cell imbalance, the balance charge you did, should fix it.

Could also be a bad battery module, which again would mean an imbalance and lower charge amps to protect the batteries.


Remember, when doing DC charging, the charger is not onboard, but the onboard charger is still responsible for regulating the wattage to the battery.

So it is the OBC that limits the current, it tells the CCS charger how much current to feed the batteries, so it is almost surely because the OBC is "mad" about something.

If the balance charge does not solve it, an MG service workshop should be able to get the car to tell, where it hurts :)
 
2 things i can think of.

1. 2000 km in 4 days, all on CCS, could make the car derate the charging due to repeated CCS charges, which can be harder on the battery, the car will derate the charge speed to protect the batteries (Well to make sure they dont go below the warranty limit, to prevent them from having to give you a new battery)

2. Loads of CCS charges = Loads of "to 80%" charges = Batteries have not been balanced. If the battery balance between cells gets to high, it might limit the current to protect the batteries.

First thing to do is....Try sticking it on a wall/home/destination AC "Charger" and set the limit to 100% and leave the car to charge until it stops and says it has finished. Then drive it and when it needs a charge, try to stick it on a CCS, if it was cell imbalance, the balance charge you did, should fix it.

Could also be a bad battery module, which again would mean an imbalance and lower charge amps to protect the batteries.


Remember, when doing DC charging, the charger is not onboard, but the onboard charger is still responsible for regulating the wattage to the battery.

So it is the OBC that limits the current, it tells the CCS charger how much current to feed the batteries, so it is almost surely because the OBC is "mad" about something.

If the balance charge does not solve it, an MG service workshop should be able to get the car to tell, where it hurts :)
Thanks for your thoughts. I did balance charge before the journey and at the first 2 of 3 overnight hotel stops. I'm booked into my dealer on 21/1 (they offered earlier but I am out of the country).
 
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