Mercedes GLC 2016 no charge

[Brahna]

Hello, i have a problem with mercedes glc 250 cdi 2016 it drained my battery once and when i tested it with multimeter i found it is not charging battery. I first changed voltage regulator then the whole alternator then the agm battery and still no charge, there is 0 trouble codes in ECU or SAM module I have 12 volts on B+ terminal and i checked continuity of terminal from alternator to ecu and its fine, every fuse is also fine i know it is ecu controlled alternator but i cant find the reason why is not charging please help

 

[DPG]

What voltage do you get at the battery when the engine is running with a few revs, and you have some accessories (lights, heated rear screen etc.) switched on?

 

[Brahna]

What voltage do you get at the battery when the engine is running with a few revs, and you have some accessories (lights, heated rear screen etc.) switched on?

Now it is 11.80 because battery is drained, no metter how many accessories are switched on battery voltage never go up only down until is drained.

 

[DPG]

Now it is 11.80 because battery is drained, no metter how many accessories are switched on battery voltage never go up only down until is drained.

And that's with the engine running?

 

[Brahna]

And that's with the engine running?

Yes

 

[DPG]

Sorry, but I'm not sure on this one - was it a new replacement alternator you fitted? And definitly the correct one?.

I'd recommend an auto electrician though rather than keep changing parts - might work out cheaper in the long run.

Hopefully some other members might have some more ideas. I'm thinking Brian Moore possibly.

 

[Brahna]

Sorry, but I'm not sure on this one - was it a new replacement alternator you fitted? And definitly the correct one?.

I'd recommend an auto electrician though rather than keep changing parts - might work out cheaper in the long run.

Hopefully some other members might have some more ideas. I'm thinking Brian Moore possibly.

Yes it was original and every nuber was same as on the old one.
Thanks anyway.