Thread: Low Battery,start engine.

Originally Posted by LandyAndy

So is there a re-set or will it fix itself with a drive????
Andrew

Hi Andrew and yours is a growing problem.

This is only in "LATE MODEL" D4s. The erroneous messages do not occur in D3s or early model D4s.

These erroneous messages are not caused by having one of my dual battery systems in stalled.

Whether you have one of my dual battery systems installed or not, the erroneous messages are caused by charging your cranking battery with a 240vac battery charger.

This problem seems to be a hit and miss occurrence, where it happens in some new D4s while others have no problems at all.

Doing a hard reset some times fixes the problem there and then but a few days later, for no apparent reason, the erroneous messages occur again.

There is also another problem occurring where for no apparent reason, the alternator voltage never gets over 12.2v and again, while a number of MECHANICS at a couple of dealerships have tried to blame my dual battery systems.

In every case it was proven that the problem had nothing to do with my systems and the fix was a simple software update.

This applies to both above situations, the erroneous messages and the low alternator voltages.

Andrew, if the erroneous messages keep occurring, then you will need to go to your dealership, and if they try to blame the dual battery system, demand to have the software updated, because there have been a number of situations where customers, after being WRONGLY told my DBS was causing the problems, the customer has disconnected my DBS and operated their D4 for a month or so and still had repeated episodes of low voltages and/or erroneous messages.

Once the dealership was informed that the D4 had not had the DBS connected since the customers last visit to the dealers, the dealer has carried out the software update and the problem has not occurred again.

Thanks Tim, your input is always appreciated.

I can tell you at least one dealer doesn't have a problem with your system. I have already had a battery replaced under warranty on my MY13 after getting many of these messages. Although I pointed it out to them, the Traxide system was never mentioned as a possible cause.

After getting a couple of these messages while camping last week, I found my new battery was only charging to about 12.5V (IIDtool measures around 14.2V when running so assume charging system is OK). I have just given it decent charge back to float level (Ctek mxs5).

Not sure if my messages are erroneous or not as an interior light may have been left on. If you are suggesting charging with a 240VAC charger is causing the problem, have you come across a better solution to restoring the battery to full charge?

Cheers,
Jon

Fixed!!!!
Drove it out of the shed,switched it off.Issue still showing.Took it for a short drive with as much electricity on as possible,ie AC full,engel on freeze,rear demister on,high-beam on.
Got home,switched everything off,then shut the car off.Normality returned,no warning .
Next time I top up the batteries I will hook up to the aux battery,just in case it upsets the BMS charging the main battery directly.
Andrew

Hi Jon and this is the weird part about these two problems. They are not common to all new D4s, just some of them.

Most owners of new D4s have no issues when charging with a battery charger and in the UK, it is now recommended that all new D4 owners invest is a battery charger, but thats another story.

Jon,did you charge the main battery directly as I did???
Andrew

Tim - and If a ctek charger is hooked up via the White towing socket, can this upset the BMS on late model cars?

Jim,if you look at the neg terminal,it appears that the BMS may not be connected to the "spare" terminal despite being fixed to it.If I hooked onto the main earth connection,which isnt that easy as its under the firewall perhaps I wouldnt have caused the problem.
Next time I will hook up to the aux battery,it will ensure the earth return goes thru the BMS.
I believe charging thru that white plug should be OK as its wired with the BMS.
UNLESS these late D4s dont like invading electrons at all
Andrew

Thanks Tim. Is this recommendation in the UK a JLR thing or a Disco4.com thing?

Originally Posted by LandyAndy

Jon,did you charge the main battery directly as I did???
Andrew

No, positive to terminal, negative to earth stud in front of battery compartment. Have since installed a Ctek plug in same location to make it easier as I expect to be doing this on a regular basis. I'm inclined to think my warnings are legitimate though, so its probably time to look into how I manage my batteries - and to start asking questions to people in low places.

IIRC, there is a way to turn off the BMS using an IIDtool (part of the ccf?). Would this help?

Cheers,
Jon