BimmerFest BMW Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
21 Posts
Discussion Starter · #1 ·
Hello dears,
I would like to get someone help because im having problems with batery chargging of my bmw 545i 2003 year. i alredy change the batettery for the new one but the problem still there seems like an alternator problem but the fult just appears when the car is started but not running if i run the car or acelerate the fault disappears if i stop the celeration the fault come again i do not understand why this are happend.
So i connect the DISV57 run the diagnostic and show me the following error code related the alternator:DME - 27DA DME: faulty alternator - Electric breakdown - defect does not exist at the moment.
i run inside this error proceed the test that give me this message:
Replace the following component:
G654 Alternator

Should i change my alternator because is broken? before i proceed with any actionsI would desperately like to hear some suggestions and opinions.

Thanks in adavance for your help
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #3 ·
Thanks for your answer sir.
I did not register the battery i just take the old one and put the new and run the car some times works fine then comes this issue when i acelerate the car and the fault gone i take the negative borne to test the alternator and car still working but with Charging Fault error on the board i try do the same thing and the car stoped work.
 

·
Registered
Joined
·
337 Posts
You must register the battery if you change it. What battery did you have before and what battery do you have now? FLA TO GLA or vice versa has to be registered so the car knows how to properly charge it.
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #5 ·
ok can i have the information how i can register the battery? this can be the reson for the Alternator fault?
 

·
Registered
Joined
·
337 Posts
I'm not 100% sure if this will cause an alternator fault. I will tell you that I have seen other posts where not registering the battery caused the car to do many weird things. You must go to the dealer to register a new battery unless you have Carly for bmw or something of that sort to be able to register the battery.
 

·
Registered
Joined
·
114 Posts
I have also learnt this. My old battery was worn and not starting the car. I replaced the battery it without registering it so still have a charging problem. The car is now with the dealer for battery registration which they said may solve the problem
 

·
Registered
Joined
·
1,263 Posts
Hello dears,
I would like to get someone help because im having problems with batery chargging of my bmw 545i 2003 year. i alredy change the batettery for the new one but the problem still there seems like an alternator problem but the fult just appears when the car is started but not running if i run the car or acelerate the fault disappears if i stop the celeration the fault come again i do not understand why this are happend.
So i connect the DISV57 run the diagnostic and show me the following error code related the alternator:DME - 27DA DME: faulty alternator - Electric breakdown - defect does not exist at the moment.
i run inside this error proceed the test that give me this message:
Replace the following component:
G654 Alternator

Should i change my alternator because is broken? before i proceed with any actionsI would desperately like to hear some suggestions and opinions.

Thanks in adavance for your help
Sounds like when you increase the engine RPM the fault goes away.

While this may be a serpentine belt slipping or a pulley problem it is more probably the voltage regulator on the alternator that is not increasing the excitation current in the alternator to maintain current output to stabilize system voltage.

If you have the electrical knowledge, test the system voltage by applying a multimeter between the jumper and ground terminals under the hood while someone revs the engine. If the system voltage increases as the engine RPM increases then the voltage regulator is defective. You may also see the system voltage increase to as high as 16V or 17V due to the defective voltage regulator.

If you are handy, purchase a replacement voltage regulator and remove your alternator from the car. First have the alternator bench tested by an auto store or shop to verify that the the alternator is indeed defective, and then swap the voltage regulator which attaches to the rear of the alternator. Bench test the alternator again to ensure it has been fixed and then reinstall the alternator and test with a multimeter again. The system voltage should now be steady at as the engine RPM is increased.

Best of luck.
 
1 - 9 of 9 Posts
Top