AX522 ABB I/O module error

I have AX522 IO module and when I power it on with 24VDC both CH-ERR2 & CH-ERR4 lights are on. I read in manual this is because of internal Error.
Please guide me to solve this problem.
best regards
Good morning :)I haven't worked on this particular PLC (but I do have experience with other brands.) Normally I would say that this message would indicate that the module has developed a hardware fault, and needs to be replaced. However, I'm assuming that it's installed in the PLC chassis, and is everything (CPU and other modules) is powered up as well.
If however it's only being powered up as a bare module (so, out of the rack, not communicating with it's CPU) then the internal error might mean simply that it can't communicate with the CPU.
Good luck!