Tail lights indicators and front brake light not working

GM doesn't have the best tail light setup. do you own a test light? You should start at the back. The turn signals and hazards use one bulb. The brake light uses another bulb. Remove the bulb and carefully test for ground and power. If it is there then it is either the bulb or related contacts. If power or ground is not there then unplug the tail light assemble and test for power or ground again. The tail light circuit board is notorious for going bad. Please start here and write back if you need further help.

You probably pinched a wire when you put the bed back on. You most likely have a blown fuse as further proof that you shorted out everything in the back of the truck.
Recheck all your wiring paths.

check for any blown bulb or fuse

I had this problem with my 2007 Honda CRV -- all the lights worked EXCEPT the tail/running lights and the license plate light. The other tail lights worked -- brake, reverse, indicators, and hazards. Front headlights also worked, but when the headlights went on the back tail lights did not (not to safe for driving at night!!)
The fuse was #15 in the interior fuse box (under the dash driver side) with the label "small exterior lights" ( also check fuse #19 labeled "small lights main"). The cause of my problem, I believe, is a bad or lose wire in my license plate light.

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Brake Lamp Replacement

Location of the lights

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The illustration shows the locations of the lights on the RH side. The LH side is the same but

mirror-reversed.

The lights have the following functions:

- 1 +1 = Parking light Fail light

- 2 = Reversing light

- 3 = Fog light LH side only (LHD cars)

- 5 = Direction indicator

- 6 = Brake light

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Tail light changing bulbs

Ignition off.

Open the cover in front of the tail light

Undo the wing nut and take out the lamp holder.

Change the defective bulb.

Fit in reverse order.

Check that all bulbs lamps are intact and in working order.

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Replacement of tail light cluster

Note! If a new tail light is to be fitted, the sleeves must be ground down 1.5 mm.

Open the cover in front of the tail light Undo the panel partly in front of the tail light Unplug the

connector for the tail light Undo the four nuts securing the tail light see illustration.

Pull the tail light straight out. Fit in reverse order

Note! check the sealing and fit on reassembly.

Check that all bulbs lamps are intact and in working order.Thank you for Using FixYa.comKind Regards, LeeYour FixYa Expert and Master Technician