Turnsignal some times the left turnsignal doesn't work on my 2005 1500 silverado, the bulbs are good.

I am just guessing at this one but you might want to check the headlight switch that turns on the headlights. Sounds like you changed just about everything else. The turn signals I believe are on a separate circuit from the brake lights. In addition you might want to check for a broken wire to turn signal harness

Sounds like a short in either the front or rear bulb, or a bad socket or even possibly a bulb installed backwards. Has anything been changed in either of these locations?

I would try to change turnsignal - brake light bulb .

You either have a bulb out, or a bad ground or a defective flasher relay.

The issue is most likely the turn signal switch.

first check the bulb to make sure the filament isn't dangling and making contact every so often, if its fine, check the socket for the bulb to be sure that its grounded correctly and both connection points are seating in the socket good

flasher relay is bad
or bad bulb

Yes, I have a 2000 model and the book says this. You will need to be prepared to move the unlock button,keyswitch, and turnsignal in this sequence.

Pull BACK on the turnsignal and hold it.
Turn the keyswitch ON,OFF,ON,OFF-

You will hear the doorlocks work.

RELEASE the turnsignal and within 10 SECONDS-

Press the UNLOCK side of the drivers doorlock 3 TIMES
Turn the key to ON, Pause, OFF

That should do it. Good Luck

replace rear left globe and this will solve both problems cheers MAL

You have a shorted bulb. Replace the bulb.