I have a 1999 dodge 2500 with the 5.9lL/360 gas engine. my drivers side turn signal will not work even after i changed the bulbs but my brake light works and i cant figure out the wireing. i looked and counted all the wires in the plugs there are 8 altogether in the plugs and i have 1 white wire that is going to nothing

take it to a body shop

The brake lights go thru the turn signal switch on most models.
If the ground is good at the socket and you have no power from the brake light switch, the problem could be in the turn signal switch.

Fast flashing dash signals mean there is a bulb issue-DEFINATELY!

bad earth on the bulb holder or the wiring, usually a good clean should sort it out.

I had the same problem that the brake light / turn signal on the right side didn't work (in the 2006 Dodge Caravan it's the same bulb). After a long search I found the problem: There was corrosion on the contact of the bulb assembly. After scraping off the corrosion everything works now.

bulbs are busted, they dont always go at the same time, so check the light bulbs

THE BRAKE LIGHTS DO GO THROUGH THE TURN SIGNAL SWITCH. TO TEST, REMOVE THE PLASTIC COVER AROUND THE THE COLUMN, UNDER THE STEERING WHEEL. THE TURN SIGNAL SWITCH MUST BE IN THE OFF POSITION. YOU WILL NEED TO EXPOSE THE WIRES UNDER THE STEERING WHEEL. DO NOT DISTURB THE WIRES IN THE YELLOW JACKET. THEY ARE AIRBAG WIRES. YELLOW PLUGS YELLOW JACKETED WIRES ARE AIRBAG.THE WIRE IN QUESTION HERE IS YELLOW BUT IT IS NOT IN A YELLOW JACKET, [ SLEEVE ]. NOW, PUSH ON THE BRAKE PEDAL. THE YELLOW WIRE IS LEFT REAR TURN & BRAKE WIRE, DARK GREEN IS RIGHT REAR TURN & BRAKE WIRE. BRAKE PEDAL DEPRESSED, IF BOTH OF THOSE WIRES HAVE POWER, ALL OF THAT IS OK. IF THE YELLOW WIRE HAS NO POWER TURN SIGNAL SWITCH IS BAD

Does any lights on the right side work? It sounds like the ground connection to the assembly is loose.

No there not connected, replace the brake light
1999 Chevrolet Blazer Auto Light Bulb Size Guide
Low Beam Headlight Bulb Size: 9006
High Beam Headlamp Light Bulb Size: 9005
Parking Light Bulb Size: 3157
Front Turn Signal Light Bulb Size: 3157
Rear Turn Signal Light Bulb Size: 3057
Tail Light Bulb Size: 3057
Stop Light Bulb Size: 3057
High Mount Stop Light Bulb Size: Assembly
Fog/Driving Light Bulb Size: 880 or 881
License Plate Light Bulb Size: 194
Back Up Light Bulb Size: 3156
Front Sidemarker Light Bulb Size: 194
Ash Tray Light Bulb Size: 161
Glove Box Light Bulb Size: 194
Map Light Bulb Size: 168 or 211-2
Step/Courtesy Light Bulb Size: 168 or 211-2
Trunk/Cargo Area Light Bulb Size: 211-2
Under Hood Light Bulb Size: 93
Instrument-General Light Bulb Size: 161 or 37 or PC194 or PC74
Check Engine Indicator Light Bulb Size: PC74
Hi-Beam Indicator Light Bulb Size: PC74
Seat Belt Indicator Light Bulb Size: PC194
Brake Warning Light Bulb Size: PC74
Automatic Transmission Indicator Light Bulb Size: 194
Directional Signal Indicator Light Bulb Size: PC74
As for the horn, inspect the fuse and relay and most common it would be a bad ground wire or worst a bad horn due to corrosion. Horn will be located in the drivers side fender.
Thank you for using fixya.

there is a relay that goes to the turn signals.......and there is a switch that goes to the brakes......check them...