It's not simple as that...... ;-)

Well.. First thing - this error appears on the trucks with LDC and LDC Combi control. Hope it's one of them.

As I've written, the batteries sometimes are really troblesome.
The voltage may look OK, but there can be other issue.
How about the electrolyte level. Has the battery the integrated filling system?
Don't believe if all the markers are up. Check underneath. The cells may be empty. Check the gravity etc.

X13:15 - X11:25 is a path between pin 13 on A2 connector (X13-121pin) and pin 25 on A1 connector (X11- 29 pin).
Just check it.

Generally this error applies to the power module, but you said, you replaced it...