Here are the likely culprits:
* Shorted Wiring Harness: This is the most probable cause. A wire in the turn signal wiring harness has likely chafed through its insulation and is touching ground or another wire, creating a short. This could be anywhere along the harness, from the fuse box to the lights themselves. The heat from the short is causing the smoke.
* Faulty Turn Signal Switch: The switch itself could be internally shorted.
* Shorted Turn Signal Light Socket: A short in the socket of one of your blinker bulbs (front or rear) is a common cause. Water intrusion can corrode the contacts and cause this.
* Shorted Turn Signal Lamp: Although less likely, a shorted bulb filament could draw excessive current and blow the fuse.
* Bad flasher unit: A faulty flasher unit can draw excessive current and cause a short circuit. However, this is less likely to cause immediate smoking.
What to do:
1. Disconnect the battery's negative terminal immediately. This is crucial to prevent further damage or fire.
2. Visually inspect the wiring harness: Carefully look for any signs of damage, melting, or discoloration, especially around the turn signal wiring. Pay close attention to areas where the wiring is bundled tightly or near moving parts. Look at both the front and rear wiring harnesses.
3. Check the turn signal switch: This is harder to inspect without some mechanical knowledge. If you see any burn marks, it's likely faulty.
4. Check the light sockets: Inspect all front and rear turn signal light sockets for corrosion, damage, or melted wiring.
5. If you're uncomfortable, take it to a mechanic immediately. A short circuit is a serious problem that needs professional attention. Trying to fix it yourself without proper knowledge could lead to injury or further damage.
Do not attempt to troubleshoot this issue further until the battery is disconnected. The smoking is a clear sign of a dangerous situation.
