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Recently I was about an hour away from home. Started the car and immediately got a "Service Charging System' on the DIC. The car was charging at 11.5 amps. I had no choice but to proceed home. Over the trip the voltage slowly dropped to 11.1, one basis point at a time. Then about 2 miles away from home, it bounced back to normal registering 14.1 amps. Is this a fluke or a precursor that I need to look into? (like replace alternator...?)
I would do a load test. I would check for a slightly loose wire on the alternator. How old is the battery. Check battery as well. Good luck and keep us posted.
From time to time I've seen the same DIC message on my 2007 A6 vert, Red. With 146,000 miles, it's on its fourth battery and second alternator. I suspect I have a corroded ground connection somewhere that's contributing. My problem usually appears on hot summer days in stop & go city traffic with coolant temps above 200 degrees. Under those conditions my charging voltage drops from 14V to just over 12V. I believe this is caused by hot rectifier diodes in the alternator. Note that Red has an E-Force supercharger which adds to the ambient under hood heat,
With all that in mind, I too suspect a loose wire in your case. The alternator connector is easy to get to. Also check the single wire lug near the connector.
As I'm sure you know, Florida's hot climate is notoriously hard on C6 batteries. Your one hour drive home with low charging voltage might have shortened its life just like any deep discharge.
Thanks guys. Its now about a month later and all WAS fine. Now I'm reading 11 volts consistently so I just replaced my alternator hoping it was that. It was 13 years old and had 123000 miles. Well, no difference. Still reading the same 11 volts.... I bought a new battery about 6 months ago but as Erito said, perhaps it was damaged.... Time to go get that checked now... (Had my BPM replaced 6 months ago. Could that be causing issues?)
Okay - so I bring the battery down to Autozone and they tell me it's okay BUT at a 7% charge and 11 volts. I don't understand the 11 volts part but they said I need to charge the battery fully and then see. It may be fine - or not. If not, then I need to drive the car over (about 5 miles) and have them load test the car's system.
What is the 11 volts part (which IS what my car's gauge was reading)? I was under the impression the battery (if all good) always charges between 12.5-14.5 volts? Can a good battery charge at 11 volts and increase as the charge gets closer to full? Could a full charge be all that is needed presuming the new alternator is working properly?
Okay - so I bring the battery down to Autozone and they tell me it's okay BUT at a 7% charge and 11 volts. I don't understand the 11 volts part but they said I need to charge the battery fully and then see. It may be fine - or not. If not, then I need to drive the car over (about 5 miles) and have them load test the car's system.
What is the 11 volts part (which IS what my car's gauge was reading)? I was under the impression the battery (if all good) always charges between 12.5-14.5 volts? Can a good battery charge at 11 volts and increase as the charge gets closer to full? Could a full charge be all that is needed presuming the new alternator is working properly?
Do you have a ohm meter handy? If so, check the battery voltage with everything off and see what it reads. Then, start the car and measure the voltage at the battery again. Not scientific but will tell you if your alternator is trying to charge the battery if second renaming is higher than the first. At rest, battery should be at 12.5 or so. Running you should see 14 or higher if all is well. Finally, check your battery cables for corrosion and tightness. Rule of thumb - it takes 20 minutes of driving at 1500 rpm to bring a good battery back up to charge just to replace the energy used to start the car!
Do you have a ohm meter handy? If so, check the battery voltage with everything off and see what it reads. Then, start the car and measure the voltage at the battery again. Not scientific but will tell you if your alternator is trying to charge the battery if second renaming is higher than the first. At rest, battery should be at 12.5 or so. Running you should see 14 or higher if all is well. Finally, check your battery cables for corrosion and tightness. Rule of thumb - it takes 20 minutes of driving at 1500 rpm to bring a good battery back up to charge just to replace the energy used to start the car!
Thanks but I dont have a volt meter. That said, I am charging the battery now. Once fully charged, is it possible that all this will be okay? The only relatively certain thing I can bank on now is the alternator isnt likely to be causing any concerns. I would have expected when I started the car after putting it in that the gauge would read 14 volts but it didnt...just 11. Would a really low charged battery cause this?...
I know this is going to sound extremely basic but have you removed the cables from the battery terminals and cleaned the inside of the clamp and the terminals?
On my '05 I had low voltage readings a lot and an occasional service charging system message but nothing was wrong. Both battery and alternator always tested good as well as various voltage readings from various points in the chain. I also had the steering wheel column lock issue a lot which is a separate issue but related when the voltage from the battery was a bit low (or at least that's my interpretation.) Removing the cables and cleaning everything to a nice shiny surface and reconnecting always increased the voltage reading in the DIC 1 or 2 volts. Until they dirtied up again and I'd repeat.
Check them and, if less than perfectly shiny, clean them really good and see what your voltage readings are.
Yep... Same problem... I did change out the alternator and battery, cleaned battery cables. Then changed out the starter last.
Strange as it sounds... I ignored everyone that said it was the starter.
Thank you, Coupe! I completely charged the battery and put it back in but havent started the car yet to see what it reads. With my luck, Im sure the problem will still be there. If it is, I REALLY appreciate your input here as now I will have another solid option to check! I'll keep you posted!
Thank you, Coupe! I completely charged the battery and put it back in but havent started the car yet to see what it reads. With my luck, Im sure the problem will still be there. If it is, I REALLY appreciate your input here as now I will have another solid option to check! I'll keep you posted!
Any update? Mine just started doing the same thing as yours...
now it wont charge above 11.8v and sometimes wont start despite a fresh battery. I haven't had time to diagnose mine yet
Had same issue and it was my starter also, had the same hole. Heat from the headers melted the plastic. replaced starter and issue gone.
Thanks. New starter has been ordered. Amazon had this AC delco for $37 on discount. Crappy thing is I don’t even have headers to blame it on. My exhaust is all stock.
02-14-2019, 02:29 PM
'Service Charging System' - yes, no, or maybe
