Turn signals fast flashing briefly when activated.

[Randyintahoe]

I did something dumb... While checking my trailer towing wiring connection I think I shorted something out. My left and right turn signals now flash fast 6-7 times before working normally. Also, the problem doesn't occur when I have the brakes on! All other lighting functions seem to work fine (no bulbs out). The emergency flashers also work without triggering the problem.

So, I could use some help with diagnostics! Thanks in advance for your help!

 

[peterk9]

Welcome to the Forum Randy.
I guess I missed your post initially. Usually, when you cause a short, a fuse will blow. Have you physically checked to see if the turn signals are actually working? A fast flash normally is an indication a bulb is burned out.

Peter

 

[Randyintahoe]

Thanks Peter. I did check the turn signal bulbs and others as well and all are fine. I wonder if a code reader could find the problem..

 

[peterk9]

Thanks Peter. I did check the turn signal bulbs and others as well and all are fine. I wonder if a code reader could find the problem..

Hard to say. I've read that some auto supply stores (Autozone?) will do a check for free.

Peter

 

[javaleo]

Autozone will NOT read all the modules. Only PCM stuff (check engine light).

I had the same problem with my left (drivers side) turn signal. I switch to LED bulbs, and I add the needed resistors on both sides. Only the drivers side did it. I removed the LED bulb and resistor and it did not happen, put just the resistor back on the circuit and still did not happen. but did with the LED blub. Now it only fast flash on the Instrument cluster, not the blubs. I used FORSCAN to turn off the "Fast Flash", fixed the problem.
Check all your blubs, you may have LEDs in the rear.

 

[peterk9]

It's called hyperflash.

Peter