Rand mcnally 730

Can someone please explain to me how to adjust the ETA on my 730 ,its way off ,everything working fine otherwise .thanks advance.

 

Ok i fixed my problem , however i would not recommend this to anyone ,im just putting this out there if you want to do it ,my rand tnd 730 i bought 5 years ago so it went threw heck and back ,so im looking for anthor new one as a back up ,bought the 740 and i cant read it with my old eyes going the road ,so back to my old one and sence it was working ,but not the eta part ,which i use a lot ,i rember going threw joilet ill lightning storm ,thats werw it screwed up ,so with that thought in mind ,heres how i fixes my eta on mine ,i found a old power chord rated a 5 v ,not enuff for the rand unit but i plug it in ,let power up ,run till screen turns white with color lines , then unplug it ,put the orginal chord back on and fired it up and now its back to normal ,with correct date month and eta and working like new again ,i kinda reversed flash the lightning storm on it or as the electric people say ,i flashed it .hopes this helps ,but like i say you may or not want to try this on new ones ,this was a old one not to worry about frying it.