In anticipation of going back to camp tonight and wanting to be able to read, I asked my husband to find his headlamp for me. He did and when he checked the batteries, he basically poured out the batteries and some liquid---it's been a while since the headlamp has been used. I decided to see if I could clean out and fix-up the battery holder before tossing the headlamp. It took cleaning, fresh batteries, and a new lightbulb but now I won't be quite so in the dark tonight!
Step 1: BoM
Step 2: Cap
The cap wasn't too bad, but did have some evidence of battery leakage. I used a q-tip dipped in vinegar to wipe away all of the fluid and build up and then wiped it down again with a damp cloth.
Step 3: Battery Holder
The battery holder was in a bit worse shape. Again, I used q-tips dipped in vinegar to clean out the gunk. When I was satisfied, went over the same areas with a q-tip dipped in water to wipe away the vinegar.
Step 4: Dry
Allow the cap and battery holder to dry before putting in new batteries.