funny acting brakelights!!

[chevy1boy24]

My blinkers are acting crazy latly. I have a 2000 chevy k2500.
when i turn on either blinker nothing happens. If I step on the brake at the same time, whichever side blinker I have on that brake light doesn't come on. "
When i turn the flashers on again nothing happens. If i step on the brake at the same time, the flashers come on, but steady.
I'"ve checked all the fuses, relays, wiring.
i know there are some relays under the dash, does anyone know if they control the flashers or blinkers? does anyone know why this is happening?
Any help would be great!

[dmarty]

Sounds like a ground problem. Check all of your grounds and ground straps everywhere, there's lots of them and the problem could be most anywhere.

[chevy1boy24]

wouldnt it be a ground somewhere connected to the tail lights ? what other grounds would affect the brake and blinker lights?

[dmarty]

You would think so, but that's not always true. Bad grounds are weird and do strange things. I had one were the heater control in the dash kept blowing fuses and not working right. Fianlly found a ground strap off between the frame and cab at the right front rubber doughnut. You can start checking all the brake light grounds, but you should also check the others. Did anything change recently on your truck? Any new wiring for a sound system or other lights? Any accident damage? If so, you should check those areas too.