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Discussion Starter #1 (Edited)
On my 2012, my welcome lights aren't turning on everytime. Maybe about 50% of time when I unlock it turns on.

Anyone know the reason why? Bad battery? FRM?
 

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On my 2012, my welcome lights aren't turning on everytime. Maybe about 50% of time when I unlock it turns on.

Anyone know the reason why? Bad battery? FRM?
****, I do not know what welcome light are since I turned all that gibberish off.
I would not say it is battery. Why they are working 50% of time? After long drive?
 

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This could be a free fix:

Headlight switch needs on auto = welcome lights.
Headlight switch in off position = no welcome lights.
 

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Discussion Starter #4
haha, definitely switch is on auto.
 

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02/2012 X5 35d M57Y CPO 100K miles NOKIAN WR G3 20K miles
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Personal Profile.
 

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Discussion Starter #6
Never changed the profile...same key, same everything.
 

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Doubt it would be a profile thing as Ace said it works 50% of the time. Maybe you have a faulty fuse that doesn't send power every single time the button is hit? (Not sure if the welcome lights have a separate fuse or not).
 

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Doubt it would be a profile thing as Ace said it works 50% of the time. Maybe you have a faulty fuse that doesn't send power every single time the button is hit? (Not sure if the welcome lights have a separate fuse or not).
LOL

"intermittant fuse"?

Do welcome lights use a signal from a daylight sensor? In other words does it need to be dark? How dark? etc etc
 

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Discussion Starter #9
No, welcome lights are supposed to be on 100% of time as long as switch is on auto
 

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I did a really quick search, nothing definitive. One common topic thougt might be a relationship between battery charge/state and will the bmw intelligent system.

If the battery is marginal, or has a margina charge, or the car thinks it is, does in prevent 'unnecessary' loads?

Do you notice any patterns? like the welcome light works after youve done same major driving...and seems not to work after a day of running around with short, 2, 5, 10 mile drives? Always works after the battery has been charged on a charger, etc?

All I got...
 

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Discussion Starter #11 (Edited)
I did a really quick search, nothing definitive. One common topic thougt might be a relationship between battery charge/state and will the bmw intelligent system.

If the battery is marginal, or has a margina charge, or the car thinks it is, does in prevent 'unnecessary' loads?

Do you notice any patterns? like the welcome light works after youve done same major driving...and seems not to work after a day of running around with short, 2, 5, 10 mile drives? Always works after the battery has been charged on a charger, etc?

All I got...
hey, thanks for this. I did a similar search and also noticed some postulates on this concept as well. Here's the weird thing that did happen two weeks ago....

I had the motor shut down, but accessories/electronics on, and I was entering some addresses into the navigation. All the sudden, the car gave me a low battery warning, and it forcibly shut down the electronics. I restarted the car, idled it for a bit and finished entering the addresses, and after that, I've had no further battery warnings.

I suppose I'll run a battery charge state test, or at least do a trickle charge tonight and see if this is the case. I last checked the battery in 2015 and it was very strong. The car however is parked outside 100% of the time and susceptible to lower temperatures, but in SF, it doesn't get cooler than 55 degrees, but there is humidity.

For 5 days a week, the car goes through a very short commute (4 mile round trips), but on weekends, it gets a lot of usage (50-80 miles over the weekend, medium distance trips, enough to cause DFP regens). The car did such a trip this weekend (used 7 gallons of diesel), and the welcome lights haven't been on for a good week now. hmmm....
 

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02/2012 X5 35d M57Y CPO 100K miles NOKIAN WR G3 20K miles
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See page 8 E70 Power Management

https://drive.google.com/open?id=0B1epIteFE7i-bk42ODJLOHc0Y00

Electric Load Reduction
When the vehicle is equipped with APM (advanced power management), in addition to increasing the idle speed and the specified charging voltage, the output of various electric loads can be reduced or the loads can be switched off in order to reduce the power consumption in critical situations.
The electric loads are shut down only under the following two conditions:
***8226; Battery charge status in critical range
***8226; Alternator fully utilized

The following measures are activated under these preconditions:
Sequence. Function. Operation. Control Unit
1. Rear Window. Clocking. IHKA
2. Seat Heating, rear compartment. Stage 2. FKA
3. Electrical auxiliary heater, rear compartment. 75 %. FKA
4. Seat heating, front. Stage 2. SMBFA SMBF JB
5. Seat heating, rear compartment. Stage 1. FKA
6. Electrical auxiliary heater, rear compartment. 50 %. FLA
7. Seat heating, front. 50 %. SMBFA SMBF JB
8. Electrical auxiliary fan, 3rd row seating. 50 %. IHKA
9. Heater blower. 75 %. IHKA/FKA
10. Electrical auxiliary heater, rear compartment. 25 %. FKA
11. Steering wheel heating. OFF. FRM/JB
12. Electrical auxiliary heater, rear compartment. OFF. FKA
13. Mirror heating. OFF. FRM/JB
14. Active seat. OFF. SMFA SMBF
15. Steering wheel heating. OFF. IHKA
16. Electrical auxiliary fan, 3rd row seating. OFF. IHKA
17. Seat heating, front. OFF. SMFA SMBF JB
18. Seat heating, rear compartment. OFF. FKA
19. Rear window. OFF. IHKA
20. Heater blower. 50 %. IHKA/FKA
21. Heated windshield. OFF. SMFA SMBF
22. Heater blower. 25 %. IHKA/FKA

Power Management includes the details of what is monitored by IBS.
Intelligent Battery Sensor
The intelligent battery sensor IBS is a mechatronic component. The IBS with its own microcontroller which continually measures the following parameters:
***8226; Battery terminal voltage
***8226; Battery charge/discharge current
***8226; Battery acid temperature
The IBS is located directly on the battery negative terminal and is used on all current BMW vehicle.
The intelligent battery sensor (IBS) is part of the power management system. The IBS is used to determine precisely the "state of charge" (SoC) and the "state of health" (SoH) of the battery.

The software in the IBS controls the process and communication with the DME (Digital Motor Electronics) control unit. The IBS sends the data via the bit-serial data interface (BSD) to the DME. The following functions are integrated in the IBS:
***8226; Continuous measurement of the battery current, voltage and temperature under all vehicle operating conditions.
***8211; When the vehicle is stationary, the measured values are interrogated cyclically every 40 s to save power. The measuring period of the IBS is approx. 50 ms. The measured values are entered in the closed-circuit current histogram in the IBS.
***8226; The state of battery charge (SoC) is partly calculated.
***8211; The DME/DDE reads out the closedcircuit current histogram after the vehicle is restarted. A corresponding entry is made in the fault code memory of the DME if a closedcircuit current infringement is determined.
***8226; The IBS sends the data via a bit-serial data interface to the DME.
***8226; Calculation of the battery indicators as the basis for the state of charge (SoC) and state of health (SoH) of the battery.
***8211; The battery indicators are charge and discharge current, voltage and temperature of the vehicle battery.
***8226; Balancing of the charge and discharge currents of the battery.
***8226; Permanent monitoring of the state of battery charge.
***8211; Transmission of date in the event of a deficit.
***8226; Calculation of the current progression when starting the engine to determine the state of battery health.
***8226; Closed-circuit current monitoring of the vehicle. (This is the function giving the Increased Battery Discharge warning.)
A "low battery warning," or Increased Battery Discharge? I have never heard of a low battery warning - that would be a real blessing indicating time to replace the battery. Increased Battery Discharge is caused by battery discharge greater than about 80 mA (varies with model) with the vehicle OFF. The advice to put the car on a booster while coding and using Ivini's Carly is likely to avoid this warning.

If your battery is so severely discharged as to cause warnings then it will require about 24 hours charging at the maximum permitted charging rate and voltage for AGM batteries. (Fast)Charging rate is not to exceed 4 Amps, charging voltage is not to exceed nominally 14.8 VDC (depending on the actual electrolyte temperature) else significant excessive gassing will occur. A 100% State of Health ZERO State of Charge 100 AH battery will require 4 Amps x 24 hours = 96 AH to be charged. A "trickle charger" is not typically capable of 4 Amps output.

The details of BMW battery testing requirements are from about page 12 of Battery Basics https://drive.google.com/open?id=0B1epIteFE7i-LU8zQW4wQmJLN3M
 

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Discussion Starter #13
Doug, thanks for the tip, I'll put the X5 on a tender tonight when I get home.
 

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02/2012 X5 35d M57Y CPO 100K miles NOKIAN WR G3 20K miles
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Doug, thanks for the tip, I'll put the X5 on a tender tonight when I get home.
Battery Tender***8482; is a Deltran trademark product with a maximum output of less than 2 Amps (last I looked). If your 100 AH battery is dead, then it will take about fifty hours on a Deltran Battery Tender***8482; to fully charge it.

Use a smart battery CHARGER like the CETEK that BMW rebrands.
 

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Discussion Starter #15
But my battery is not completely dead..
 

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In hindsight, mine did this quite a bit. I made note of it every Monday when I ran the same errands and would pull into the same parking spot at the same time and the reflection in a store window would show the halo lamps on, then the next week off. I ran the carly app alternator output gauge and one during one period the output dropped to approx 12 volts then jumped to 14. One time when programming, the app would not run because it claimed the battery was at 12.4 volts, while the car was running, then the output jumped to 14 and i programmed the stop lights.
 

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Discussion Starter #17
my wife disclosed to me this morning that she got the increased battery discharge warning almost every day for the last two weeks, and she didn't tell me....then she claimed that she told me 2 weeks ago....

Anyways, the X5's on a tender all day today and we'll see how it goes.
 

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my wife disclosed to me this morning that she got the increased battery discharge warning almost every day for the last two weeks, and she didn't tell me....then she claimed that she told me 2 weeks ago....

Anyways, the X5's on a tender all day today and we'll see how it goes.
Ah.... The staff these days...

;)
 

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Discussion Starter #19
I'm glad to report that the welcome lights now work consistently after charging the battery.
 
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