Hi all,
Car: Mercedes GLC 250D 2017 (Coupe) - 4Matic (UK Model)
Engine: OM651.921
I will try and keep this sweet and short for you guys.

• My dad's car is currently having battery related issues. Car completely lost electrical power inside car, we jump started battery, didn't hold charge long enough, died again.
• Took the battery out of the car and put another battery in from a different GLC, car starts and has power, made it to home, then that battery now dies. So for me it was a no brainer that it was the alternator.
• Got the new alternator, had it changed with the old battery fully charged back into the car, still same issue.

Does the alternator require any sort of programming of sort? (I have xentry)
Can anyone give me other ideas for what I can check?

So far spent £370 for parts and labour for alternator plus £60 car recovery costs.

Any help will be appreciated.

 

If you have Xentry you should have WIS, read it and see if it needs coding.
How about to check a voltage ?

 

When I changed my alternator, no peogram was needed.

Voltage, while the engine running, must be around between 14.4 ~15v at the battery terminals. If not, new but faulty alternator or check connection.

 

Thanks for replying back.

After further looking at all the fuses and connections we started to divert attention to belt and pulleys.

And we think we’ve found the problem now, the crankshaft pulley is non functional(broken) compared to the donor glc we have which sounds like the cause of the problem.

Yet to order part and will report back if that is the issue.