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Was the BMS module reset when the battery was replaced? If you have a multimeter, you can check the voltage across the battery prior to starting then once started to check, in simple terms, if the alternator is providing any output. The charge current from the alternator is controlled by the BMS module so the output will vary as it charges and discharges the battery under normal operation. There's a few threads to have a read through as a few have had battery/alternator issues recently.
The voltage on my old battery was 12.4 volts with ignition off and 14 volts with engine running. Any idea how to reset BMS ?
 

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Hi, you either need to go to a garage that has equipment that will do this, or do as I did and buy the iCarsoft LR V2.0 code reader as below. It has many other uses as well. Phil
 

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Hi, you either need to go to a garage that has equipment that will do this, or do as I did and buy the iCarsoft LR V2.0 code reader as below. It has many other uses as well. Phil
So now can i simply clear the codes with icarly and register my new battery with it? or do i need to disconnect the terminals or charge the battery or in worst case scenario get another battery and repeat the procedure?
 

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Buy an icarsoft V2 follow the instructions, it is the easy and safe way to reset the BMS and it will give you the fault codes, and reset them.
 

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Buy an icarsoft V2 follow the instructions, it is the easy and safe way to reset the BMS and it will give you the fault codes, and reset them.
just ordered it from amazon for £151 coming on monday, will update you.. thank you ☺
 

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Hi, if you have any problems with it please post again and I will try to help. Phil
 

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just checked with icarsoft. i have tried resetting the battery and clear the codes but still no luck. at one point it said no faults then under diagnosis it said 19 faults, i cleared all of them but still park brake fault remained. idk what is causing the issue but when i changed the battery everything suddenly went away, so i’m assuming it’s the small battery or the alternator which isn’t charging the battery.
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Was the BMS module reset when the battery was replaced? If you have a multimeter, you can check the voltage across the battery prior to starting then once started to check, in simple terms, if the alternator is providing any output. The charge current from the alternator is controlled by the BMS module so the output will vary as it charges and discharges the battery under normal operation. There's a few threads to have a read through as a few have had battery/alternator issues recently.
just reset the bms with icarsoft diagnostics tool but still the park brake fault is there, not sure if it’s the small battery or the alternator which isn’t charging the battery but the volts are perfect on diagnostic tool but definitely everything went away as soon as i got new battery.
 

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The BMS takes ages to catch up with real world facts..it basically talks about facts in the past and as such is fairly useless imho..

I don't think it would have anything to do with your park brake problem though...
 

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The BMS takes ages to catch up with real world facts..it basically talks about facts in the past and as such is fairly useless imho..

I don't think it would have anything to do with your park brake problem though...
oh yes there’s definitely nothing wrong with parking brake. just need to figure out what could be the issue because the brand new battery fixed all errors and the eco start stop was working fine aswell but the next morning everything came back up.
 

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does anyone know how to check if an alternator is gone? if it’s not alternator then it’s the small battery or could be bms which is attached on negative terminal
 

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Red light on the dash stays on if the alternator is kaput I believe.
 

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just checked again after leaving it off for 5 hours. the battery voltage doesn’t go above 12v and when i turn the climate or lights on it goes down to 11v .
i have attached pictures aswell.
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These are the following codes im getting, when i clear all of them , turn the car off and turn it back on everything stays fine until i press the brake pedal and the park brake fault comes on and when i keep pressing the brake pedal the other fault comes on aswell. im assuming it’s because of the low voltage because alot of sensors are connected through brake and abs correct me if im wrong.
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Your battery voltage is seriously low, very likely causing these issues. First thing is to get the battery recharged. Connect your charger to the positive terminal and a suitable earth point, NOT the negative battery terminal. Get some decent charge into the battery then recheck the voltages once the battery has rested for a few hours, without starting the engine, then check voltages with the engine running. Next will be to ascertain if the low battery voltage was due to something draining it, the alternator not charging correctly or a duff new battery.
 

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i’ll try to recharge the battery tomorrow morning but this is a brand new battery. do you think there could be something which is draining the battery? i made sure everytime that all doors are shut properly and all lights are off.
 

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ido you think there could be something which is draining the battery?
These cars usually shut down and modules go to sleep mode without issues, I don't think I've noted one that didn't, unlike some old Range Rovers....... Maybe if you'd left a key inside or close it may be possible every time it timed out it wakes again, or didn't enter sleep? I'm not sure these cars scan for a key without the door handle or start button being operated, maybe someone else can advise? I wouldn't be surprised if you found your alternator has failed and it's coincidence your old battery was 10 years old, though at that age it needed changing anyway. The BMS does control the alternator charge current so it's not as simple as cars once were to figure a failing alternator. The BMS will allow the battery to go to quite a low charge before fully recharging it, there's a thread here somewhere with the full details. Also it's in the workshop manual, charging description, if you've downloaded it.
 

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These cars usually shut down and modules go to sleep mode without issues, I don't think I've noted one that didn't, unlike some old Range Rovers....... Maybe if you'd left a key inside or close it may be possible every time it timed out it wakes again, or didn't enter sleep? I'm not sure these cars scan for a key without the door handle or start button being operated, maybe someone else can advise? I wouldn't be surprised if you found your alternator has failed and it's coincidence your old battery was 10 years old, though at that age it needed changing anyway. The BMS does control the alternator charge current so it's not as simple as cars once were to figure a failing alternator. The BMS will allow the battery to go to quite a low charge before fully recharging it, there's a thread here somewhere with the full details. Also it's in the workshop manual, charging description, if you've downloaded it.
can’t find the workshop manual, a link to it will be highly appreciated. Thanks
 
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