My 2009 Holden Cruze petrol alternator is not charging the battery

This is the problem with just replacing parts without knowing the actual cause of the problem. If the third alternator and third battery haven’t solved the charging problem, obviously you need to look elsewhere. If a brand new alternator and a brand new battery aren’t talking to each other, you clearly have a break in communication somewhere in the middle.

Start with the battery terminals and cables. Are they tightly connected to the battery and not frayed or broken beneath the plastic insulation? Sometimes there’s a fusible link (a fuse, basically) built into the battery terminal that will break to protect the electrical system if there’s a short circuit somewhere. That’s worth a check too. The fusible link is usually contained within the battery terminal itself.

The next step is the check all the fuses and relays that connect the battery and alternator with the rest of the car. These can accessed via the fuse-box which is usually located under the glovebox or behind the kick-panel in the footwell, but there’s often also a second fuse-box under the bonnet. Sometimes the cause of non-charging can even be as simple as the little red warning light on the dashboard that has blown its globe, although that’s not often the case with more modern cars like yours.

If you still can’t figure it out, an auto electrician is your next stop, rather than simply throwing more new parts at the car which may or may not fix it.