Thanks for all your valious help partners, i´m sure it´s not a battery problem, ´cos i found a way to make the instrument pass the Auto zero initial test but it´s not a technical way :p and the instrument keep working normally, the problem is that if i shut down the instrument, when i turn it on again it presents the CO2 error code again.
I´m really sure the problem is in the pressure transducer it needs to be recalibrated or something.
Thank´s for all, with all the valious help that you have given me i´m sure i will fix this problem.
