www.tdiclub.com

Economy - Longevity - Performance
The #1 Source of TDI Information on the Web!
Forums Articles Links Meets
Orders TDI Club Cards TDIFest 2016 Gone, but not forgotten VAG-Com List Unit Conversions TDIClub Chat Thank You




Go Back   TDIClub Forums > VW TDI Discussion Areas > TDI 101

TDI 101 Got a simple/basic TDI question? Are you a newbie (new to the forums). Feel free to post your question here.

Reply
 
Thread Tools
Old January 19th, 2019, 16:15   #1
charlieruu
Veteran Member
 
Join Date: Jun 2016
Location: Marquette, MI
Fuel Economy: who cares
Default Battery not charging emergency

Hey all, yesterday I went to start my car and the battery was dead so I got it jumped and all was good. Later that night I was driving around and the immobilizer light was flashing at me followed by the airbag light. I've had this happen before when my alt died on me except that time the alternator light was on. I checked the voltage while running on my scanner app and it was at 9.4 volts. It recently got very cold here (under 0 degrees F) so I'm thinking something stopped working or broke because of this. I tried to check today to look for any loose connections and there were none. The battery is fairly new from VW dealership and the alternator is also new (<7k miles). The positive battery cable has also been replaced. This car has given me so many problems with not charging and I'm not sure what to do this time. I fear that a shop will just tell me I need a new alternator and maybe I do but I want to rule as much out as I can. Where should I start?
charlieruu is offline   Reply With Quote
Old January 19th, 2019, 16:40   #2
jettawreck
Veteran Member
 
jettawreck's Avatar
 
Join Date: Aug 2004
Location: Northern Minnesota-55744
Fuel Economy: 52+ average lifetime '01
Default

Sounds like the alternator (or the internal regulator) is done. Nothing beats a physical bench test to check how it handles a load and output.
__________________

2001 Jetta TDI GLS Silver-current driver (salvage)permanently vented-Panzer Plate-Sprint 520s-ScanGauge-CheckTemp III-ZeroStart heater-CAT 2 filter
2003 Jetta GLS Black w/leather (New Project Car) fixer-upper w/broken TB
2004 Cadillac SLS (wife's)
1999 GMC Suburban (It's MN-you need one)
197? Shibura 2cyl diesel 4WD tractor-loader/brushhog (very handy unit)
196? International TD340 Dozer-w/Drott 4-in-1 bucket/back ripper attachment
jettawreck is offline   Reply With Quote
Old January 19th, 2019, 17:02   #3
Mongler98
Veteran Member
 
Join Date: Mar 2011
Location: Northern MD
Fuel Economy: Race: 12mpg, Gandma:65mpg
Default

Get volt meter, and test it yourself, or take it to auto zone and have it tested.
A volt meter with an amp draw function will tell you everything you need to know. If your battery is good, cables bad, connections, charging and so on. $10 bucks usually will do.
Mongler98 is offline   Reply With Quote
Old January 19th, 2019, 17:18   #4
JesseTDI
Newbie
 
Join Date: Nov 2018
Location: Liberty, Mo
Default

Most alternators and batteries have 12month 12k mile warranties you might get it replaced under that coverage if your lucky.
JesseTDI is offline   Reply With Quote
Old January 19th, 2019, 17:55   #5
Mongler98
Veteran Member
 
Join Date: Mar 2011
Location: Northern MD
Fuel Economy: Race: 12mpg, Gandma:65mpg
Default

Quote:
Originally Posted by JesseTDI View Post
Most alternators and batteries have 12month 12k mile warranties you might get it replaced under that coverage if your lucky.
I hate non OEM parts but some times, its worth going with parts with these warranties especially when OEM parts are hard to come across same day.
Case in point, my 04 escape EATS starter motors about every year or 2. Napa has a no hassle life time on all there parts. The guy i purchased the escape from back in 2014 had put it in. I have his folder of all the receipts and work done, took the starter in with the receipt, new starter for free, and have done this twice now. never pay for this part again. Granted it did leave me stranded 450 miles away from home once, BUT i was next door to a NAPA and had to wait till they open.
Mongler98 is offline   Reply With Quote
Old January 19th, 2019, 18:48   #6
joetdi
Veteran Member
 
Join Date: Mar 2008
Location: Midwest
Default

Quote:
Originally Posted by Mongler98 View Post
Get volt meter, and test it yourself, or take it to auto zone and have it tested.
A volt meter with an amp draw function will tell you everything you need to know. If your battery is good, cables bad, connections, charging and so on. $10 bucks usually will do.
Your're going to need a little more than a volt or amp meter to test this. You need to put a draw on the alternator.
joetdi is offline   Reply With Quote
Old January 19th, 2019, 19:05   #7
Ol'Rattler
Veteran Member
 
Ol'Rattler's Avatar
 
Join Date: Jul 2007
Location: Marysville, Wa.
Default

Quote:
Originally Posted by joetdi View Post
Your're going to need a little more than a volt or amp meter to test this. You need to put a draw on the alternator.
The OP has 9.4 volts charging voltage. Is there some magical test equipment that would tell him why? What would this test equipment draw? a picture of Mr. McGoo?
__________________
2006 Jetta TDI
5 speed, Manufactured 06/06
DC stage 1 SMF Clutch
Draw-Tite hitch
Dash Tray
Blue tint aspherical mirrors
Euro Cupholder
Euro Light Switch
2nd grocery hook
VCDS Hacks: DRL Disabled-Seatbelt Chime Disabled-Key fob Power Windows
Adjusted Cam to Crank Timing
Ol'Rattler is offline   Reply With Quote
Old January 19th, 2019, 19:11   #8
joetdi
Veteran Member
 
Join Date: Mar 2008
Location: Midwest
Default

Quote:
Originally Posted by Ol'Rattler View Post
The OP has 9.4 volts charging voltage. Is there some magical test equipment that would tell him why? What would this test equipment draw? a picture of Mr. McGoo?
You full field the alt to see if all you need is a reg and not also a stator or retifier.
joetdi is offline   Reply With Quote
Old January 19th, 2019, 19:19   #9
Mongler98
Veteran Member
 
Join Date: Mar 2011
Location: Northern MD
Fuel Economy: Race: 12mpg, Gandma:65mpg
Default

Quote:
Originally Posted by joetdi View Post
Your're going to need a little more than a volt or amp meter to test this. You need to put a draw on the alternator.
9.4 amps, regulator is bad or a soldering point within the unit.

Rebuild or replace.
no load drawing needed to test this.
Mongler98 is offline   Reply With Quote
Old January 19th, 2019, 19:23   #10
joetdi
Veteran Member
 
Join Date: Mar 2008
Location: Midwest
Default

Reg is not going to a help a bad stator.
joetdi is offline   Reply With Quote
Old January 19th, 2019, 19:27   #11
joetdi
Veteran Member
 
Join Date: Mar 2008
Location: Midwest
Default

If you want to replace the whole alt you could do that
joetdi is offline   Reply With Quote
Old January 19th, 2019, 22:36   #12
Ol'Rattler
Veteran Member
 
Ol'Rattler's Avatar
 
Join Date: Jul 2007
Location: Marysville, Wa.
Default

Quote:
Originally Posted by joetdi View Post
Reg is not going to a help a bad stator.
Why do you assume that a low charging voltage is because of the alternators rectifier diodes? Still, an ohmmeter would tell you if you have diodes shorted or open.

Quote:
Originally Posted by joetdi View Post
If you want to replace the whole alt you could do that

A lot of people replace there OEM alternators with garbage re-mans and end up replacing those garbage remans time after time after time when they could have polished the slip rings, replaced the brush/regulator assembly and clutched pulley on their OEM alternator and been good for at least 100K miles more.

No, you don't need a crap ton of diagnostic equipment if you understand how things work and how to troubleshoot those things. One of the most bogus diagnosis tools I have heard of is the bull **** battery load tester auto parts stores have. The only way it's test is valid is if you have a battery charged 100% prior to testing.
__________________
2006 Jetta TDI
5 speed, Manufactured 06/06
DC stage 1 SMF Clutch
Draw-Tite hitch
Dash Tray
Blue tint aspherical mirrors
Euro Cupholder
Euro Light Switch
2nd grocery hook
VCDS Hacks: DRL Disabled-Seatbelt Chime Disabled-Key fob Power Windows
Adjusted Cam to Crank Timing

Last edited by Ol'Rattler; January 19th, 2019 at 22:46.
Ol'Rattler is offline   Reply With Quote
Old January 19th, 2019, 22:52   #13
Ol'Rattler
Veteran Member
 
Ol'Rattler's Avatar
 
Join Date: Jul 2007
Location: Marysville, Wa.
Default

Quote:
Originally Posted by Mongler98 View Post
9.4 amps, regulator is bad or a soldering point within the unit.
Rebuild or replace.
no load drawing needed to test this.
Right arm Bro. At 9.4 Volts, no need to make something simple and obvious into a science experiment. If an alternator does not develop 12+ volts, how would the added stress of a load test give you diagnostic data that would lead to repairing the problem? In such a situation, you might find that the brushes are shot and arcing which will destroy the slip rings even more when you load up the alternator with your not needed load test.

And that's the problem with VCDS. So many people will shout to the stars about how completely awesome and necessary VCDS is and will have absolutely no clue into how to actually diagnose something even with the invaluable information VCDS provides.

For those that don't know, VCDS does not tell you what to replace. It tells you what the ECU sees that you need to diagnose to find out why the ECU set the code.
__________________
2006 Jetta TDI
5 speed, Manufactured 06/06
DC stage 1 SMF Clutch
Draw-Tite hitch
Dash Tray
Blue tint aspherical mirrors
Euro Cupholder
Euro Light Switch
2nd grocery hook
VCDS Hacks: DRL Disabled-Seatbelt Chime Disabled-Key fob Power Windows
Adjusted Cam to Crank Timing

Last edited by Ol'Rattler; January 19th, 2019 at 23:16.
Ol'Rattler is offline   Reply With Quote
Old January 19th, 2019, 23:24   #14
Ol'Rattler
Veteran Member
 
Ol'Rattler's Avatar
 
Join Date: Jul 2007
Location: Marysville, Wa.
Default

Almost forgot. How is your battery not charging an emergency to anyone but you?
__________________
2006 Jetta TDI
5 speed, Manufactured 06/06
DC stage 1 SMF Clutch
Draw-Tite hitch
Dash Tray
Blue tint aspherical mirrors
Euro Cupholder
Euro Light Switch
2nd grocery hook
VCDS Hacks: DRL Disabled-Seatbelt Chime Disabled-Key fob Power Windows
Adjusted Cam to Crank Timing
Ol'Rattler is offline   Reply With Quote
Old January 20th, 2019, 06:45   #15
joetdi
Veteran Member
 
Join Date: Mar 2008
Location: Midwest
Default

Apparently you don't know what full fielding an alt does, with respect to the reg as you don't need a fully charged battery.

A guy next to me was working on a like vehicle as mentioned here. He measures about 9.6 volts. So based on Mongler's statement above he puts a OEM alternator on the car. He measures 9.8 now. So, it must be bad one right? So, he puts another OEM on and now he's really close to 10 volts.

What you think was wrong with this car and how did he find it.

And no it wasn't another bad alternator.
joetdi is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Battery / generator light on, alternator not charging, battery holds charge Keven VW MKIV-A4 TDIs (VE and PD) 16 December 12th, 2013 14:22
Battery not charging NeilO TDI 101 8 June 6th, 2011 22:26
Battery Light Blinking Battery Not Charging, Hard To Start hardmeat VW MKIV-A4 TDIs (VE and PD) 3 November 2nd, 2009 16:56
Battery not charging AARodriguez Corp. TDI 101 2 July 2nd, 2009 14:04
charging battery? jjtkcep TDI 101 6 June 28th, 2009 13:01


All times are GMT -7. The time now is 16:03.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright - TDIClub Online LTD - 2017
Contact Us | Privacy Statement | Forum Rules | Disclaimer
TDIClub Online Ltd (TDIClub.com) is not affiliated with the VWoA or VWAG and is supported by contributions from viewers like you.
1996 - 2017, All Rights Reserved
Page generated in 0.17202 seconds with 11 queries
[Output: 129.92 Kb. compressed to 108.73 Kb. by saving 21.20 Kb. (16.32%)]