inputs.text: cautious nav present already - not work still give head unit great review two reasons clean looking says problehem not clear breakdown really no ones fault hopefully help someone not make mistake said done used car dealer excellent unit upgrading factory radio nav vehicle already nav typically backup camera also unit not work vehicles already wired upgrades not wired match systehem unit upgrades mind buying oehem unit tundra limited installed tundra base model amfm cd along nav worked ideally little tricky without instructions fortunately professional install cannot help good unit money upgrade not replacehement