Home Forums Articles How To's FAQ Register
Go Back   Xoutpost.com > BMW SAV Forums > X5 (E53) Forum
Arnott
User Name
Password
Member List Premier Membership Search Today's Posts Mark Forums Read

Xoutpost server transfer and maintenance is occurring....
Xoutpost is currently undergoing a planned server migration.... stay tuned for new developments.... sincerely, the management


Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 11-22-2020, 02:48 PM
Member
 
Join Date: Sep 2014
Location: California
Posts: 309
Johnny_5 is on a distinguished road
Question 04 X5 battery light coming on and off

So got into my X today and noticed that the battery light came on after warming it up and went off and came back on and off again. I did a battery test with my scanner cycling it with lights on and turning off and on as well as alternator check holding at 2000 etc and everything checked out fine. Does this mean that the alternator may be going out? I’ve also been having 4x4 light coming on occasions if that matters.

Any advice would be greatly appreciated.
__________________
2004 X5 4.4i 202k on odometer
Reply With Quote

Sponsored Links

  #2  
Old 11-22-2020, 03:09 PM
andrewwynn's Avatar
Member
 
Join Date: Jun 2015
Location: Racine, WI
Posts: 10,817
andrewwynn will become famous soon enough
It's almost always the alternator. The slip rings and brushes specifically.

Monitor real time voltage as you coast to stop from 30 mph.

If the voltage drops even 1/2 a volt the alternator is not doing its job.

When it happened to me the voltage dropped enough that the abs trifecta kicked on.

I replaced my brushes and slip rings on mine and did just the bushes and changed the polarity of the brushes so the other slip ring would take the abuse and add years to the lifespan.
__________________
2011 E70 • N55 (me)
2012 E70 • N63 (wife)
Reply With Quote
  #3  
Old 11-22-2020, 03:31 PM
Member
 
Join Date: Sep 2014
Location: California
Posts: 309
Johnny_5 is on a distinguished road
Quote:
Originally Posted by andrewwynn View Post
It's almost always the alternator. The slip rings and brushes specifically.

Monitor real time voltage as you coast to stop from 30 mph.

If the voltage drops even 1/2 a volt the alternator is not doing its job.

When it happened to me the voltage dropped enough that the abs trifecta kicked on.

I replaced my brushes and slip rings on mine and did just the bushes and changed the polarity of the brushes so the other slip ring would take the abuse and add years to the lifespan.
Sounds like you rebuilt yours. Do you have a link to how you did it and parts list by any chance? Would love to get to it this coming weekend if all goes well.

Lately cars been acting weird no tri errors but have had the 4x4 and abs kick on. I thought it might have been that known gear issue but now I’m leaning to electrical.
__________________
2004 X5 4.4i 202k on odometer
Reply With Quote
  #4  
Old 11-22-2020, 11:31 PM
Member
 
Join Date: Oct 2013
Location: on earth
Posts: 1,150
puddinboo is on a distinguished road
More than likely low voltage causing those lights to come on.
Quote:
Originally Posted by Johnny_5 View Post
Sounds like you rebuilt yours. Do you have a link to how you did it and parts list by any chance? Would love to get to it this coming weekend if all goes well.

Lately cars been acting weird no tri errors but have had the 4x4 and abs kick on. I thought it might have been that known gear issue but now I’m leaning to electrical.
2003 BMW X5 E53 M54 engine,253512KM
__________________
2003 bmw x5 3.0i ,219000km build date 2003-08-18
Reply With Quote
  #5  
Old 11-23-2020, 03:46 AM
andrewwynn's Avatar
Member
 
Join Date: Jun 2015
Location: Racine, WI
Posts: 10,817
andrewwynn will become famous soon enough
Search in advanced for awr-fix in title and andrewwynn user.

I rebuilt just the slipring and brushes but have very detailed photos of the steps.

I had valeo alternators and the kit to repair is about $20 on eBay. With the Bosch I've not seen the equivalent kit. That said most of the wear is just the brushes so If you remove the VR you can disassemble and find the brush size and find a replacement set.

Look for my latest one where I swapped the brush polarity because if the slip rings are not terribly worn you dont even need to replace if you swap the polarity of the bushes it's not difficult just a couple inch long jumper wires.
__________________
2011 E70 • N55 (me)
2012 E70 • N63 (wife)
Reply With Quote
  #6  
Old 11-23-2020, 10:58 AM
Member
 
Join Date: Nov 2018
Location: Canada
Posts: 634
c-bass is on a distinguished road
Quote:
Originally Posted by Johnny_5 View Post
So got into my X today and noticed that the battery light came on after warming it up and went off and came back on and off again. I did a battery test with my scanner cycling it with lights on and turning off and on as well as alternator check holding at 2000 etc and everything checked out fine. Does this mean that the alternator may be going out? I’ve also been having 4x4 light coming on occasions if that matters.

Any advice would be greatly appreciated.
Your ODB scanner? Or you have an actual battery tester device?

Most auto parts stores should be able to test the battery for you. Don't rule out the battery unless you get a proper test done on it.
Reply With Quote
  #7  
Old 11-23-2020, 11:10 AM
Member
 
Join Date: Jun 2013
Location: Virigina, USA
Posts: 2,573
StephenVA is on a distinguished road
Johnny 5
The reasons why the light flickers is based on the charging system seeing voltage dropping below a predetermined threshold like 12Volts.
Testing what is going on is the only way to determine if you have a Battery issue or a Charging issue.

Listed below is the way to test a starting system (battery/starter/wiring) and a charging system (alternator, wiring, computer control systems)

Starting & charging systems testing techniques
Here are a few quick tests to determine a battery issue, a charging system issue, or a primary wiring issue.

Skill Level: 2 + (read and follow instructions)
Tools required: Digital Volt Meter (DVM), battery terminal cleaning tool, and 8mm, 10 mm sockets and ratchet with extensions.

You need to read battery voltage before starting any test on an electrical system as it will influence the results of Starting, Charging, and electrical tests of any kind. (Note: battery must be fully charged, see chart below).

Step one: Get out a digital volt meter, Read battery voltage (Key off). Read voltage (Key on) at the following points Battery, under hood jump point, and at the alternator. You only need to determine if you have 12 volts at the alternator with the key on (BIG FAT WIRE). A simple handheld digital wave form tester will get you in the ball park when it comes to batteries. (Further discussion on these testers is for another engineering forum).
Step Two: You need to read the voltage at the BATTERY at idle, 1500, and 2500 RPM to determine voltage regulator function. Better still would be a Volt Amp tester (VAT-40 Image below) to induce a correct AMP load to read actual AMP/Volt output from the alternator and battery, as that is the only true testing method. Having a DVM that has min/max capability will make your testing easy.
Step Three: Remove and clean each and every ground in the trunk, jump point, and at the frame rail for the block (bad grounds = lots of electrical issues). Clean the starter/alternator cable connection under the car, just under the dead pedal.
Step Four: Failure to get correct output on running test means DEAD alternator (volt regulator, brushes, windings, etc.) Remove and bench test the unit or drag it to your local auto parts store for a second opinion (which will be worth exactly what you pay for it....)

Base line numbers
Battery Voltage should be 12.6+V (Key off) See chart below.
Battery voltage should be 13.5v - 14.5v on running tests (note large fluctuations at running RPMs is a SURE sign that the Volt Regulator is not doing its job. Smack with rubber hammer and retest. Rebuilt units have large variance of quality control from good 85% of the time to approx 50/50%.

NOTE: The exact charging voltage will vary according to the battery's state of charge, the load on the vehicle's electrical system, and temperature. The lower the temperature the higher the charging voltage, and the higher the temperature the lower the charging voltage. The "normal" charging voltage on a typical application might be 13.8 to 14.3 volts at 77 degrees F. But at 20 degrees F. below zero, the charging voltage might be 14.9 to 15.3 volts. On a hot engine on a hot day, the normal charging voltage might drop to 13.5 to 14.3 volts.

Note 2: TIS specifies alternator voltage as 14.3 +/-0.1 V. But that is measured at the alternator output post. The values seen using the cluster will be 0.5 V or more below the alternator voltage output.

Battery Surface Charge.

What the heck is a surface charge?
When testing wet cell auto batteries, some will show a 12.xx Volt result, but as soon as a 100-150 amp load is applied, they drop straight down to 9.8V or lower. Classic example of a collapsed cell wall (internal short). This is why too many DIY and techs get stumped when they pull out a meter and say "It shows 12.xxV so it must be good”. NOPE, batteries are tested for voltage holds and AMP draw capacity as well as the ability to recover and recharge over and over again. Batteries are nothing more than an energy storage device. The challenge is for the average DIY to approx. the load test with KEY OFF.

Solution: Set a volt meter to DC volts 0-25 scale or auto ranging if so equipped. Read and record voltage
Turn on everything in the car for 15 seconds:
Headlamps to high beam
Heater blower motor to high w/ A/C on
Seat Heaters
Rear Defroster (and rear seat blower if so equipped)
Interior lights
Radio
Fog lamps
Cigar lighter
etc, etc, etc

Read voltage after testing. You should see a drop off of .5-1.5Volts during the test and a slow rise back to 12.5V+ on a completely healthy and fully charged battery in 30sec to 1 min.

A battery that is DEAD, will show 9.8V or less and never recover until charged.


Battery Registration: There is NO battery registration required for proper operations in a E39 or E53 application.

Alternator testing tips
How to load the alternator at engine idle for alternator output tests if you do NOT own a VAT:

Note: Alternator output should be tested with the engine idling under the following four loads after at least 15 seconds of idling (for the alternator to ramp up):
Turn the high beams on
And, turn the rear defroster on
And, turn the fan on (full)
And, turn the wipers on (to the regular setting, I guess)

These loads should be left on while the alternator output tests are being performed.

Once access to the alternator is gained (access for the I6 is vastly easier than the V8):

• Check the voltage from the alternator #30 post and ground
o It should be the same as the battery voltage
• Now disconnect the harness connector to the alternator:
• Check voltage from terminal 15 and ground (field voltage)
o It should be the same as the battery voltage

ANOTHER QUICK CHECK FOR BOSCH ALTERNATORS

One way to check the integrity of the alternator and diodes on Bosch alternators is to check the voltage readings at the D+ (blue wire) terminal and B+ terminal. The voltage reading should be the same at both terminals. A difference of more than one volt would indicate faulty diodes and the need to replace the alternator.
Tips link: https://www.diyauto.com/manufacturer...ion-by-bluebee

Volt Drop Testing (Image below) will show you issues with grounds and wiring problems. Read the text and test a few spots to determine if your car has clean connections.
https://www.engine-light-help.com/voltage-drop.html

Are you having other electrical issues? Alternative issues: Ignition Key switch failure, wiring junction box rusted (see water leaks under passenger seat (E39), Water standing in trunk under the battery (E53) and the normal wiring broken connectors, grounds), etc....

Tip Sites for more info:
https://www.aa1car.com/library/2002/cm10220.htm
https://www.bimmerfest.com/forums/sh...d.php?t=510579 (Everything you wanted to know about BMW starting and charging systems for DIY)
Need a Video? https://video.search.yahoo.com/searc...d&action=click

Helpful?
Attached Images
     
__________________

2005 X5 4.8IS
The Blue ones are always FASTER....

Current Garage:
2005 X5 4.8is
2002 M5 TiSilver
2003 525iT
1998 528i
Former Garage Stable Highlights
2004 325XiT Sport
1973 De Tomaso Pantera, L Model
1970 Dodge Challenger T/A 4 sp Alpine White
1970 Dodge Challenger T/A 4 sp GoManGo Green
1971 Dart Sport, “Dart Light” package
1969 Road Runner 383
1968 Ply Barracuda 340S FB Sea-foam Green

Last edited by StephenVA; 11-23-2020 at 11:19 AM.
Reply With Quote
  #8  
Old 11-24-2020, 12:40 AM
Member
 
Join Date: Jul 2016
Location: Menlo Park, CA
Posts: 2,311
Fifty150hs is on a distinguished road
Quote:
Originally Posted by Johnny_5 View Post
So got into my X today and noticed that the battery light came on after warming it up and went off and came back on and off again. I did a battery test with my scanner cycling it with lights on and turning off and on as well as alternator check holding at 2000 etc and everything checked out fine. Does this mean that the alternator may be going out? I’ve also been having 4x4 light coming on occasions if that matters.

Any advice would be greatly appreciated.
That's what happens right before your alternator dies.
Reply With Quote
  #9  
Old 11-24-2020, 11:40 PM
Member
 
Join Date: Sep 2014
Location: California
Posts: 309
Johnny_5 is on a distinguished road
Quote:
Originally Posted by puddinboo View Post
More than likely low voltage causing those lights to come on.

2003 BMW X5 E53 M54 engine,253512KM
Yea Im thinking thats the case as well. I wasn't able to get to it due to work and holidays but I need to get to it asap.

Today coming back home my air bag stabilizer light came on. Turned off the car and turned it back on and it went away.

Quote:
Originally Posted by andrewwynn View Post
Search in advanced for awr-fix in title and andrewwynn user.

I rebuilt just the slipring and brushes but have very detailed photos of the steps.

I had valeo alternators and the kit to repair is about $20 on eBay. With the Bosch I've not seen the equivalent kit. That said most of the wear is just the brushes so If you remove the VR you can disassemble and find the brush size and find a replacement set.

Look for my latest one where I swapped the brush polarity because if the slip rings are not terribly worn you dont even need to replace if you swap the polarity of the bushes it's not difficult just a couple inch long jumper wires.
Will do thank you. Might need to get to it this coming weekend!

Quote:
Originally Posted by c-bass View Post
Your ODB scanner? Or you have an actual battery tester device?

Most auto parts stores should be able to test the battery for you. Don't rule out the battery unless you get a proper test done on it.
My OBD2 scanner just a regular hand held unit is what i used. I tested both battery and alternator holding at 2000, turning off and on, turning on headlights, etc....it made me do the cycles to confirm. Im sure its not 100% but its better then what other units do. I know its nothing compared to the actual testers.

Quote:
Originally Posted by Fifty150hs View Post
That's what happens right before your alternator dies.
Yea Im probably going to get to it this weekend hopefully. Need to read up on andrewwynn post on how he rebuilt it and what he used. Im sure it would be better then just getting a generic auto parts store alternator
__________________
2004 X5 4.4i 202k on odometer
Reply With Quote
  #10  
Old 11-24-2020, 11:43 PM
Member
 
Join Date: Sep 2014
Location: California
Posts: 309
Johnny_5 is on a distinguished road
Quote:
Originally Posted by StephenVA View Post
Johnny 5
The reasons why the light flickers is based on the charging system seeing voltage dropping below a predetermined threshold like 12Volts.
Testing what is going on is the only way to determine if you have a Battery issue or a Charging issue.

Listed below is the way to test a starting system (battery/starter/wiring) and a charging system (alternator, wiring, computer control systems)

Starting & charging systems testing techniques
Here are a few quick tests to determine a battery issue, a charging system issue, or a primary wiring issue.

Skill Level: 2 + (read and follow instructions)
Tools required: Digital Volt Meter (DVM), battery terminal cleaning tool, and 8mm, 10 mm sockets and ratchet with extensions.

You need to read battery voltage before starting any test on an electrical system as it will influence the results of Starting, Charging, and electrical tests of any kind. (Note: battery must be fully charged, see chart below).

Step one: Get out a digital volt meter, Read battery voltage (Key off). Read voltage (Key on) at the following points Battery, under hood jump point, and at the alternator. You only need to determine if you have 12 volts at the alternator with the key on (BIG FAT WIRE). A simple handheld digital wave form tester will get you in the ball park when it comes to batteries. (Further discussion on these testers is for another engineering forum).
Step Two: You need to read the voltage at the BATTERY at idle, 1500, and 2500 RPM to determine voltage regulator function. Better still would be a Volt Amp tester (VAT-40 Image below) to induce a correct AMP load to read actual AMP/Volt output from the alternator and battery, as that is the only true testing method. Having a DVM that has min/max capability will make your testing easy.
Step Three: Remove and clean each and every ground in the trunk, jump point, and at the frame rail for the block (bad grounds = lots of electrical issues). Clean the starter/alternator cable connection under the car, just under the dead pedal.
Step Four: Failure to get correct output on running test means DEAD alternator (volt regulator, brushes, windings, etc.) Remove and bench test the unit or drag it to your local auto parts store for a second opinion (which will be worth exactly what you pay for it....)

Base line numbers
Battery Voltage should be 12.6+V (Key off) See chart below.
Battery voltage should be 13.5v - 14.5v on running tests (note large fluctuations at running RPMs is a SURE sign that the Volt Regulator is not doing its job. Smack with rubber hammer and retest. Rebuilt units have large variance of quality control from good 85% of the time to approx 50/50%.

NOTE: The exact charging voltage will vary according to the battery's state of charge, the load on the vehicle's electrical system, and temperature. The lower the temperature the higher the charging voltage, and the higher the temperature the lower the charging voltage. The "normal" charging voltage on a typical application might be 13.8 to 14.3 volts at 77 degrees F. But at 20 degrees F. below zero, the charging voltage might be 14.9 to 15.3 volts. On a hot engine on a hot day, the normal charging voltage might drop to 13.5 to 14.3 volts.

Note 2: TIS specifies alternator voltage as 14.3 +/-0.1 V. But that is measured at the alternator output post. The values seen using the cluster will be 0.5 V or more below the alternator voltage output.

Battery Surface Charge.

What the heck is a surface charge?
When testing wet cell auto batteries, some will show a 12.xx Volt result, but as soon as a 100-150 amp load is applied, they drop straight down to 9.8V or lower. Classic example of a collapsed cell wall (internal short). This is why too many DIY and techs get stumped when they pull out a meter and say "It shows 12.xxV so it must be good”. NOPE, batteries are tested for voltage holds and AMP draw capacity as well as the ability to recover and recharge over and over again. Batteries are nothing more than an energy storage device. The challenge is for the average DIY to approx. the load test with KEY OFF.

Solution: Set a volt meter to DC volts 0-25 scale or auto ranging if so equipped. Read and record voltage
Turn on everything in the car for 15 seconds:
Headlamps to high beam
Heater blower motor to high w/ A/C on
Seat Heaters
Rear Defroster (and rear seat blower if so equipped)
Interior lights
Radio
Fog lamps
Cigar lighter
etc, etc, etc

Read voltage after testing. You should see a drop off of .5-1.5Volts during the test and a slow rise back to 12.5V+ on a completely healthy and fully charged battery in 30sec to 1 min.

A battery that is DEAD, will show 9.8V or less and never recover until charged.


Battery Registration: There is NO battery registration required for proper operations in a E39 or E53 application.

Alternator testing tips
How to load the alternator at engine idle for alternator output tests if you do NOT own a VAT:

Note: Alternator output should be tested with the engine idling under the following four loads after at least 15 seconds of idling (for the alternator to ramp up):
Turn the high beams on
And, turn the rear defroster on
And, turn the fan on (full)
And, turn the wipers on (to the regular setting, I guess)

These loads should be left on while the alternator output tests are being performed.

Once access to the alternator is gained (access for the I6 is vastly easier than the V8):

• Check the voltage from the alternator #30 post and ground
o It should be the same as the battery voltage
• Now disconnect the harness connector to the alternator:
• Check voltage from terminal 15 and ground (field voltage)
o It should be the same as the battery voltage

ANOTHER QUICK CHECK FOR BOSCH ALTERNATORS

One way to check the integrity of the alternator and diodes on Bosch alternators is to check the voltage readings at the D+ (blue wire) terminal and B+ terminal. The voltage reading should be the same at both terminals. A difference of more than one volt would indicate faulty diodes and the need to replace the alternator.
Tips link: https://www.diyauto.com/manufacturer...ion-by-bluebee

Volt Drop Testing (Image below) will show you issues with grounds and wiring problems. Read the text and test a few spots to determine if your car has clean connections.
https://www.engine-light-help.com/voltage-drop.html

Are you having other electrical issues? Alternative issues: Ignition Key switch failure, wiring junction box rusted (see water leaks under passenger seat (E39), Water standing in trunk under the battery (E53) and the normal wiring broken connectors, grounds), etc....

Tip Sites for more info:
https://www.aa1car.com/library/2002/cm10220.htm
https://www.bimmerfest.com/forums/sh...d.php?t=510579 (Everything you wanted to know about BMW starting and charging systems for DIY)
Need a Video? https://video.search.yahoo.com/searc...d&action=click

Helpful?
Thank you for the very detailed posting. I may try to do that on Thursday while Im off work. Im really thinking its the alternator but would suck to change it and to find out its not it. But honestly all the lights that have been coming on lately really makes me think its the alternator. Im sure its the original alternator and the X miles are pretty up there. Battery was replaced last year if I recall correctly.
__________________
2004 X5 4.4i 202k on odometer
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On





All times are GMT -4. The time now is 12:46 PM.
vBulletin, Copyright 2024, Jelsoft Enterprises Ltd. SEO by vBSEO 3.6.0
© 2017 Xoutpost.com. All rights reserved. Xoutpost.com is a private enthusiast site not associated with BMW AG.
The BMW name, marks, M stripe logo, and Roundel logo as well as X3, X5 and X6 designations used in the pages of this Web Site are the property of BMW AG.
This web site is not sponsored or affiliated in any way with BMW AG or any of its subsidiaries.