2010 LR2 .25A draw kills battery
#11
11-21-2022, 12:55 AM
When the battery is drained the Voltage can dip too low while the starter motor is engaged.
The LR2 has a lot of modules that can latch up and then not shut down upon command when this happens.
I did get a warning light for the headlight leveling module once but it was due to a drained battery and after disconnecting the battery and charging it and then reconnecting everything was fine (Note: I may have replaced that battery soon after that)
Don't forget to do a hard reset (disconnect both leads at the battery and allow the Voltage of the LR2 to drop to Zero then reconnect)
And your LR2 may never go into sleep mode unless you lock it (which is difficult to do unless everything is closed)
The sleep mode will take sometime post locking.
Good luck
Paul
PS don't forget to bypass the fiber-optic connection of the modules with the loop back and also remove the electrical connection.
The LR2 has a lot of modules that can latch up and then not shut down upon command when this happens.
I did get a warning light for the headlight leveling module once but it was due to a drained battery and after disconnecting the battery and charging it and then reconnecting everything was fine (Note: I may have replaced that battery soon after that)
Don't forget to do a hard reset (disconnect both leads at the battery and allow the Voltage of the LR2 to drop to Zero then reconnect)
And your LR2 may never go into sleep mode unless you lock it (which is difficult to do unless everything is closed)
The sleep mode will take sometime post locking.
Good luck
Paul
PS don't forget to bypass the fiber-optic connection of the modules with the loop back and also remove the electrical connection.
She's been disconnected since I discovered she went completely dead except to start and move her (as it didn't make sense to allow a massive draw while connected) , and charge the battery each time. I've managed to improve the full charge stabilized no load voltage of the "not that old" battery from 12.18 to 12.49v with repeated "repair mode" charging using my Noco Genius g26000 charger.
Noco claims it's a microprocessor controlled de-sulfation charge cycle using higher voltages while disconnected from the vehicle as an attempt to improve battery status.
Next time I start her up I'll be sure the multimeter is on it so I can monitor voltage drop while cranking. I'll put more "repair" charge cycles over time while disconnected, hoping the voltage readings (taken after at least 8hrs with nothing connected) improve to closer to 12.6v if at all possible.
I also put the charger on the battery in normal "mode" while checking for the draw with the meter between the neg post and the ground cable because when I 1st started, it read ~4A then gradually dropped down in steps over time to a steady .25A, which I assume is what's draining it.
Thanks again Paul.
Jay
#12
11-23-2022, 01:27 PM
Jay,
I prefer to use the term Voltage Dip (Battery can't supply the Volts ) instead of Voltage Drop (Voltage difference between two points with a current flowing)
For reference here is the VoltageDip at the battery when cranking
(note: my volt meter has a MIN function and that is what I used)
LR2________11.07 Volts (New battery)
A4 2.0T_____10.64 Volts MFG --> April 2019
328i________10.20 Volts Original battery from 2015
Jetta 1.8T____10.53 Volts Original battery from 2015
If you are in the 11.0 Volts or higher while cranking then I would continue to use that battery
Below 10.5 Volts and it is time to consider replacement
Here is the link that I originally posted
https://www.freel2.com/forum/topic37...ht=voltage+dip
Good Luck
Paul
I prefer to use the term Voltage Dip (Battery can't supply the Volts ) instead of Voltage Drop (Voltage difference between two points with a current flowing)
For reference here is the VoltageDip at the battery when cranking
(note: my volt meter has a MIN function and that is what I used)
LR2________11.07 Volts (New battery)
A4 2.0T_____10.64 Volts MFG --> April 2019
328i________10.20 Volts Original battery from 2015
Jetta 1.8T____10.53 Volts Original battery from 2015
If you are in the 11.0 Volts or higher while cranking then I would continue to use that battery
Below 10.5 Volts and it is time to consider replacement
Here is the link that I originally posted
https://www.freel2.com/forum/topic37...ht=voltage+dip
Good Luck
Paul
#13
11-24-2022, 01:58 AM
Jay,
I prefer to use the term Voltage Dip
Below 10.5 Volts and it is time to consider replacement
Here is the link that I originally posted
https://www.freel2.com/forum/topic37...ht=voltage+dip
Good Luck
Paul
I prefer to use the term Voltage Dip
Below 10.5 Volts and it is time to consider replacement
Here is the link that I originally posted
https://www.freel2.com/forum/topic37...ht=voltage+dip
Good Luck
Paul
Yes voltage dip makes more sense as voltage drop would be the drop seen between any resistance. I'd planned on getting back to working on it Thursday in between kitchen duties so will discover more then.
Hope everyone has a great Thankgiving holiday!
Jay
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