ML63 Charging Problems
 

I bought a 2007 ML63. 6.2.

I noticed in the service parts-records it had already had two alternators – all genuine MB parts. After taking delivery and a few days driving, I noticed the voltage indicator showing 12.4-12.6V… after a decent amount of driving including a 200mile trip.

The symptom was “a slight dip” in engine cranking speed before it sped up and started. NEVER failed to start.

I got it checked at my independent garage - MB conversant – and they said “weak battery”.

So the battery was changed for a MB battery. No improvement.

Then a few weeks later I took it in for a replacement alternator and belt – MB Genuine – slight improvement in the charging voltage showing… showing 13.4V after a 10-12 mile drive… but still that “slight engine cranking speed dip” at the start of the cranking cycle… symptomatic of a lazy starter.

Then after a few months, I got the starter changed – MB Genuine. We noticed the alternator to earth cable was FORD – changed that to MB Genuine. (this will not affect it… but MB is MB…).

The starter behaviour is better… but the charging voltage is still low… and now – I am out of ideas…

Any ideas/suggestions? Car has NEW MB Battery, alternator and starter.

Nawaz Khan