Hello, I have a 2004 Ford F150 XLT. One week ago when signalling to turn, the clicker was fast. The front flashers flash normal speed, but the side view mirror and rear signals flash fast. Then the problem went away. There are no burned out bulbs.

Now it has progressed, as gremlins do, to fast or slow or no flashers working when I press on the brake pedal. When I take my foot off the brake, all is normal again. When I put my foot on the brake, I have fast flashers in the rear and side view mirrors as well as faint rear brake lights. And further progression, sometimes if I press on my brake pedal it all stops and I have no flashers. And of course today they are working normally.

We have gone through ALLDATA electrical diagrams (some) but don't think it's the multifunction switch as the brake is not connected to this switch. We haven't gotten to deciding if the flash indicator switch or control junction box may be the cause.

Another post, "Turn signals freaking out" seemed very similar to my problems and the response was a grounding issue : "lost a ground and getting feedback through other circuits" or "need a new flasher module".

I live on an acreage and drive rough roads - not sure if this causes a ground issue? Can someone clarify for me what a ground issue is and where this flasher module is? Where do I begin to look? I am trying to either fix this myself this week or have all the information ready for when my husband returns from Sin City in one week so he can tackle this. He is an electrical engineer so he would understand the responses related if I don't.

THANKS for any assistance!
Jenn

 

i have seen this caused many times by corrosion in the trailer plugs, check both the 4 pin and the 7 for green death or damage.

 

Agree, Has to be a plug if the the bulbs are working