A/c doesn't start after installation navi head unit
 

Hi guys,ι have a honda accord 2005 here in greece,and i upgrade my old simple head unit stereo to navi head (2006) unit together with the wiring harness original part honda from e-bay.Everything works perfect but i have a problem....a/c doesn't start when touching command on at the touch screen!!(A/C operating normally with the old unit)
Am i doing it wrong that I bought 2006 navi head unit ,and not the 2003-2005 version???
I am very upset because the sun burns from now on greece...please any help :(
Thank's.

could certainly be an issue with you buying the wrong year head unit. the controls are quite specific.

did you disconnect the battery negative after the install to reset everything?

No!Should be done to work the unit??:)

any time you do anything to the electrical unit you should disconnect the negative post. Two times installing head units I have come across the A/C not working afterwards. Both times I forgot to plug the A/C control harness back in.

Thanks for the advice!