i recently bought an 89 gmc jimmy with a kenwood stereo/cd player in it,and i had to change the battery in it and then my radio won't work anymore,all i get is code,and i tried to get ahold of the old owner but no luck there.if anyone could help i would be forever greatful.all i can read on the unit is y 9150-15,the model # is kdc 319 thank you . john a hill jr hillbrothersauto@yahoo.com