I have installed projector headlights with xenon bulbs and LED turn signal lights.
The turn signals flash rapidly, and I have even installed resistors to try to correct this, but to no avail. Any ideas on how this might be corrected.
Is it true that the signal flasher is computer controlled and the dealer can adjust it.
Or, is there a flasher module that needs to be changed?

Any ideas will be greatly appreciated. All works well with the original incandescent bulbs.

 

The PCM controls turn signals (and lots else). All the new trucks are very finicky about electric load, resistance, etc. The LED lamps draw less and confuse the PCM. You should have the dealer apply the snow plow lighting update to the PCM and see if that fixes the issue. That update was designed to allow different lighting loads.

 

2008 LED Lighting
https://www.fleet.ford.com/truckbbas...tml/Q158r1.pdf

Snowplow
https://www.fleet.ford.com/truckbbas...tml/Q155R1.pdf

2011 LED lighting
https://www.fleet.ford.com/truckbbas...ml/Q-158R2.pdf


the whole list
https://www.fleet.ford.com/truckbbas...s/hotinfo.html

 

Thanks loads to bnmcoy for those links!