Passenger headlight won't turn on

ummm the MAIN ground connection off the battery (the chassis ground) has a spot where the lug from the battery attaches...wirebrush that spot to remove all corrosion...the lug also must be made shiny from the wirebrush...bolt 'em together and enjoy a full 12.5 volts to the chassis~

five years is about the life span of these new tin/antimony alloy car batteries~

I already put new battery in 7months ago, but I'll try that out tomorrow over work. But I'm still open to more questions!

It's an 88. You could have a wire with a rotted coating that's cracked and the bare wire could be touching another piece of metal causing a short or just plain out burnt wire running from that headlight. Chase the wires and check for green corrosion at the connection points too. If there is green corrosion and the length of wire between the connection points is still in tact take the connectors off clean them with your wife's nail file and put some cooking oil on the connectors to help prevent that green coating from coming back. If that's not it, buy a flashlight and tape it to the flip thing. Just remember to turn the flashlight off when you park. Your batteries will die.

And the wires I'm referring to are from the headlight to the power source.