Turn signal light on right stays on, won't blink, ...

Get the left signal to flash fast then walk around the car to see which light isn't flashing then change the bulb or socket if they all appear to be flashing (front and rear) turn on the right turn signal then look into the front and rear lens and count the number of bulbs flashing, now do the same thing on the left. Many times there's more than 1 bulb in each lamp. I hope this helps. Take care.

It would be easier to answer if new what kind of truck you have as far as test light staying on and not blinking sounds like you are not on the correct pin turn your flashers on and check each pin should have 2 pins blink right and left if not look in fuse box and check for a blown fuse most likely under hood copartment trailer turn signals

Generally speaking, symptoms of a bad or failing turn signal bulb are usually the culprit...in your case, either it's the front left or rear bulb. Varies for different vehicle makes...common signs include:

1. turn signal light staying on solid
2. or blinking very fast
3. or either sides of the bulbs stop blinking altogether.

To test this, make sure you reconnect everything you disconnected.
Turn the left signal light on; go to the front of the vehicle, is the turn signal bulb illuminated? If it lights up, even though it is not blinking obviously the bulb is okay. If it doesn't, replace it- problem solved. You'll do the same procedure for the rear turn signal Is that lit up? If not replace the bulb and the problem is solved.
Another common failure is when the turn signal blinks really fast, same procedure as mentioned above.
If both bulbs for the left side and right side illuminate but don't blink, the problem is in the steering column turn signal switch.
If the left or right side blinkers don't work properly at all...then check the integrated hazard warning/turn signal flasher relay- that may be defective; again, that's usually the case if both sides of the signal light don't work.
If you are blowing any fuses related to the flasher system, you have an electrical overload in the turn signal circuitry.

lol sounds like my old truck most likely crossed wires

Sounds like a bad ground to me, although i am no expert.
i would be checkinh all connections and take it from there, a little wd40 might just solve it short term.

Replace the circuit board on the left rear tail light ***.This can be purchased at a NAPA auto parts store.(this is where the bulbs are fasten into)

In this situation you should realy take it to a reputable auto electric shop. Good luck

bad turn signal switch I think

The other turn signal bulbs are blown, or the turn signal unit itself is bad. it is under the dashboard and makes the ticking noise when the turn signal is on.

relay is bad turn signal relay