The tail light wiring harness in the cargo area is not protected very well. As a result it may become damaged due to normal wear a tear. This damage can causing some or all of the rear lights to stop working.Google+
Car Problem Reports
Chevrolet Express 1500 Tail Light Wiring in Cargo Area May be Damaged
Chevrolet Express 1500 Problem
Average Mileage: 105,940 mi (31,000 mi - 189,000 mi)
Visitor, 2002 Chevrolet Express 1500
We have a chevrolet express 1500 year 2002. When the brakes are on and the van is off the tail lights turn on, the thing is when we turn the van on and head lights on the tail lights don't turn on at all. DOES ANY ONE KNOW what we can do to fix this any ideas.If any one can tell us how to re wire or fix this in anyway we thank you so much.
Rear break liight randomly stops working.
Visitor, 2002 Chevrolet Express 1500, 143,761 mi
My problem was the brake lights not functioning when the headlights were on. My fix: After numerous test of the rear wiring harnesses both right and left (checked for wire continuity and shorts), I found a short in the rear wire harness on the passenger side (actually the short was in the brake light socket itself). I replaced the wiring harness (autozone Part #923-015 - $22.99) and now the brake lights work properly. I'm a happy camper now.
Good luck, hope this helps.
Visitor, 2000 Chevrolet Express 1500, 60,000 mi
Tail lights would go out or high light worked, but low light didn't, bulbs were not blown. AFter inspecting the housing found that GM would spot weld the ground through the plastic housing to the wire. Both sides ultimately failed. Ended up cutting through the lamp housing, cleaning off the molten plastic and making a good connection to the ground.