Member Since: 12 Oct 2007
Location: In the cack
Posts: 6488
D4 BMS possible issue
So the D4 is 5 years old and I've started to replace everything that's getting tired and worn. Over the last few weeks I've noticed the D4 labour a bit whilst cranking so I started to monitor the battery voltage using the IID tool. This not only give you the battery voltage but also the current and shortly after start up the in rush current was around the 60-70amp mark, this quickly drops down to 10amps or so. My thinking at this point is the alternator is pretty healthy but the battery is dying so off I go to Eurocarparts for a new one. After fitting the new Exide EA1000, non AGM as I don't have start/stop, I reset the battery option in Service/Test menu of the IID tool so the car knows I've spent more money on her and should be grateful, I start her up and watch the voltage and current values. After about 10 mins the current has dropped from +30amps to -21amps with the engine running. I'm thinking the alternator has been cooked due to the new battery accepting a high level charge for a longer period. I just wanted to check everything was as should be around the battery area and that both terminals where done up tight so I gave it another going over and yes everything was spot on. Just out of curiosity I disconnected the two pin connector that plugs into the BMS and immediately the engine dropped revs for a split second then sounded normal. I reconnected the lead and the engine sounded laboured like when you connect jump leads to a flat battery. Checked the IID tool and the battery estimated SOC had jumped from 80% to 100% and the current was showing 34 amps and voltage 14.6v. Anybody want to take a punt and why this happened?
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22nd Dec 2015 3:47 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
Posts: 17932
I've no idea about the alternator health yet but you have confused the BMS somewhat.
I suggest you charge the battery with it not connected to the vehicle, then connect it and then reset the BMS with the IID. That way everything should be back to normal.
The BMS is supposed to let a new battery discharge before recharging it again so it can learn the new characteristics, so the behaviour you observed was probably normal.
I still recommend AGMs for the D4, even without stop-start.
Land Rover - Turning Drivers into Mechanics Since 1948
Member Since: 12 Oct 2007
Location: In the cack
Posts: 6488
Cheers Robbie
I tested the battery before fitting with a Fluke and it showed 12.68v so didn't see the need to give it 49 lashes with the CTEK. The BMS has definitely thrown a wobbler but hopefully it's now back on track. It could save people a few quid if they think the battery is dying but really it's the BMS that needs a "refresh".
The Exide comes with a 4 year warranty and was recommended on ECP's and Tanya's website so if it goes tits up before the 4 year mark then happy days. It was only £75 including VAT and it's a better spec than the original with 100Ah capacity and 900CCA Club Exped trailer
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22nd Dec 2015 4:14 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
Posts: 17932
The Exide is a great battery and when members ask me to fit a battery to a D3 I don't fit anything else. The BMS system just plays a bit more nicely with an AGM battery. Indeed, some of the early weirdness of the BMS was 'fixed' by JLR by fitting AGMs under warranty.
The Exide should be better than the original offering though and I am sure everything will settle down. If it does not then use the IID to take a recording of the parameters over time as snapshot readings mean very little on the D4.
Why does my spiel chucker want to change Exide to Exorcism?
Land Rover - Turning Drivers into Mechanics Since 1948
Member Since: 03 Nov 2009
Location: Greater Venice
Posts: 2025
Re: D4 BMS possible issue
Ent wrote:
How do I display this view on my MY2011 D4?
Is it the "finger in the middle of the top grey bar for 5s, and then 5s in the top left corner" (Code is 753 )?Discovery 5 tdv6 HSE Corris Gray Outback Engineering Limited Edition IID Pro MV License
31st Oct 2016 7:58 pm
Skarre
Member Since: 13 Oct 2016
Location: Österskär
Posts: 36
I'm also qurious as how to get that display to show.
ANd I also have BMS issues. Did you get it sorted in the end?
26th Mar 2017 6:24 pm
DSL Keeper of the wheelie bin
Member Since: 11 May 2006
Location: Off again! :-)
Posts: 73092
Me too.
26th Mar 2017 6:29 pm
Skarre
Member Since: 13 Oct 2016
Location: Österskär
Posts: 36
Ok, I just took another shot at the BMS (not litterally, however that's definetly an option at this point). I pulled the connector to the BMS and the numbers on my IID started jumping around. The voltage stayed the same at 12,2 but the battery charge percentage dropped from 81% to 51%. When I connected it again the percentage stayed at 58, wich is basically what 12.2 is. 58% of a fully charged battery (actually it was 12.28 according to my voltmerer). I have now connected a charger again and hopefully the BMS will allow it to be charged to a proper 100%. Fingers crossed!
Also I've connetcted the charger to a point between the BMS and the earth. Between the BMS and the earth wire there is a flat metal piece so I attachted the clamp to that. This means the BMS gets all the data it needs during charging now... hopefully.
Ill let you know tomorrow how it went.
26th Mar 2017 6:58 pm
Skarre
Member Since: 13 Oct 2016
Location: Österskär
Posts: 36
Battery charged. A good 12,7V.
When I first attached the cable and then plugged in the BMS the IID showed 90%, but only 12V! Then it dropped to 65% but showed 12,2V.
The car still shows low voltage and flashes 12.2V on the instrument display. Same voltage on the IID. When measuring the battery with earth attached to battery it shows abou 12.4V.
The weird thing is 12,2V is closer to 35% than 65% (ignore my previous post, I checked and 12.2V is way lower than I thought). But 12,4V is 60%. So it seems it reads the value on the battery as 65% which is basically correct, but still shows 12.2V (or even 12.0V) which is just plain wrong. But the whole system reacts to this low voltage reading and starts shutting things down, like the rear camera and park assist.
The battery is checked and should be fine. Just had i changed and it should be just fine.
Any ideas? Is it the BMS? Could i be a bad ground cable?
27th Mar 2017 9:14 pm
B7adh
Member Since: 05 Nov 2012
Location: Halifax w/yorks
Posts: 9
Does anyone know Where abouts is the bms located? The brown blue and brown wire connected to the positive battery terminal has been pulled aggressively and snapped the wire on my vehicle causing a charging fault. I cannot find the other end to repair, pulled out the battery and fuse relay box and no sign of the other end, even removed the tape off the loom and separated all the wires.. Also two severed wires that I presume are the transport connector which are not needed. Also i have noticed two prongs on the negative battery clamp which also looks to have had a connector/wires attached. I bought this as a stolen recovered vehicle and looks like the thieves have pulled the wires thinking they were a tracking device. Any help appreciated.
8th Jan 2022 1:26 am
tzdisco4
Member Since: 12 Jan 2016
Location: Lower Saxony
Posts: 10
Re: D4 BMS possible issue
Ent wrote:
So the D4 is 5 years old and I've started to replace everything that's getting tired and worn. Over the last few weeks I've noticed the D4 labour a bit whilst cranking so I started to monitor the battery voltage using the IID tool. This not only give you the battery voltage but also the current and shortly after start up the in rush current was around the 60-70amp mark, this quickly drops down to 10amps or so. My thinking at this point is the alternator is pretty healthy but the battery is dying so off I go to Eurocarparts for a new one. After fitting the new Exide EA1000, non AGM as I don't have start/stop, I reset the battery option in Service/Test menu of the IID tool so the car knows I've spent more money on her and should be grateful, I start her up and watch the voltage and current values. After about 10 mins the current has dropped from +30amps to -21amps with the engine running. I'm thinking the alternator has been cooked due to the new battery accepting a high level charge for a longer period. I just wanted to check everything was as should be around the battery area and that both terminals where done up tight so I gave it another going over and yes everything was spot on. Just out of curiosity I disconnected the two pin connector that plugs into the BMS and immediately the engine dropped revs for a split second then sounded normal. I reconnected the lead and the engine sounded laboured like when you connect jump leads to a flat battery. Checked the IID tool and the battery estimated SOC had jumped from 80% to 100% and the current was showing 34 amps and voltage 14.6v. Anybody want to take a punt and why this happened?
...
Hi,
this behavior is pretty usual, if it is not to cold. I observed this on my MY12 D4, too. If a new or completely charged battery is mounted and a reset is made via IIDTool, the BMS starts almost immediately to discharge the battery down to 80-84% estimated charge in order to enable recuperation. This is done when throttling and/or braking happens by increasing the generator voltage in order to charge the battery, and the opposit happens when speeding up again. Whilst driving on a level surface the voltage of the generator is limited around 12.6-13.1 Volts with almost zero charging/discharging current.
And you can only charge a battery with a significant amount of current if it is not fully charged. I've once seen 100 Amps charging current while throtteling when going down a hill. 100 Amps at 14.7 Volts make 1,47 kW charging power.
When the outside temperature is low enough to start the FFBH this recuperation process is not happening. Just to make the next cold crank.
Regards,
Thomas
11th Jan 2022 10:25 am
ronp
Member Since: 29 Nov 2006
Location: North Yorkshire
Posts: 15264
^ you are replying to a post/issue that’s over 6 years old.
First post ….. welcome to the forum Thomas. ...... always on the road less travelled 🚧
11th Jan 2022 10:41 am
tzdisco4
Member Since: 12 Jan 2016
Location: Lower Saxony
Posts: 10
Well, indeed. I'm wondering why I could see this thread as I haven't searched for sth like that. Sorry. But many thanks for your welcome .
Thomas
ps. Just saw that someone popped it up on the 8th ...
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Well, indeed. I'm wondering why I could see this thread as I haven't searched for sth like that. Sorry. But many thanks for your welcome 
.
