D40 not working/alarm

I have a 200L and the D40, when I connect the 2 units together using the supplied cable, the D40 immediately gets a flashing green charging light and a solid red alarm light indicating reverse polarity according to the manual. I don’t have any load plugged into the DC output Anderson connecotor. I have tried connecting the Anderson connector to my RV fuse panel, which works and powers all my appliances fine with my AC200MAX - and nothing works. Tried reversing polarity and same issue.

Incidentally, the manual shows connection POS and NEG on the Anderson connector when hooking up the fuse panel??

Hi @Timjowers, Based on your description, we haven’t identified any issues.

We recommend upgrading the firmware to the latest version. Please let us know the test results after upgrading.

Could you record a video when the issue occurs? After that, please upload it to a cloud service, then share the link with us.
Additionally, we’d like to know the AC200MAX’s error history. This information will help us identify the root cause of the issue.