hi, just picked up a 08 v-6 f150 stx. Nice clean truck, I noticed the hazzards are not working right . only the left front works. all other lights work blinkers ,brakes ,tail ect..
After doing some checking out the 4 pin plug has been cut and a new 4 pin plug with wires has been run straight to the rear tail lights on both sides .
Not using the the factory harness at all. Should i remove the the 4 pin running straight to the tail lights so i can start at a begining point,and check all of the fuses . i think the trailer fuse blew and the guy before me just wired straight to the tail lights . thanks for any help

 

You have a good starting point. Remove the non factory item before moving on diagnoses.

Who knows what the grounding is on the added 4 pin plug.

In the hauling and towing forum there is a sticky, which I do believe has the part number for the 7 pin / 4 pin combo plug to the connector under the truck, so you can replace it.

 

so its a good chance that could have something to do with the hazzards.
He had the white ground wire just hanging there not connected.
thanks.

 

It is difficult to diagnoses the truck functions with an unknown added to the mix. If the ground wire is just hanging, that tells you the splices to the tail lamps might not be the best.

When you remove the duct tape solution, double check that the wires are OK from the bulb socket, past the turn under the truck. Make there is not something else added to the harness under the rear of the truck, but the bumper.

 

fuse# f42 is not listed in the pic of the fuse box in the owners manual . Its listed in the fuse list chart as a left trailer stop turn lamp. aim i missing some thing

 

Good catch, the 2008 1st printing, the box for F42 is blank in the PDF version ( page 301, upper left hand corner next to R201 & perpendicular to F01 ).

Here is the 2007 2nd printing, fuse layout ( page 275 ), the orientation is 90* rotated anti-clockwise, so F42 is shown in the lower left hand corner ( still by R201 & F01 )

 

thanks !!! going to mess with it tonight

 

checked all the fuses 2 of the trailer fuses were out one 20 and one 10- red and yellow.
still have only one hazzard light blinking the front left only? i think i have checked all of the dailey light fuses . all lights work. except the right front and rear lights when the hazzards are on.any ideas to check next?

 

If you have the stop / turn on each rear working correctly and the turn work on the front correctly, the only other thing is the MFS.

The hazard switch is a plastic push down, that slides another plastic switch into the side of the MFS ( if memory serves me correctly, the 97-03 MY were this way ).

Remove the MFS, and check with this chart ( watch the connector numbers )

 

Thanks for the help.. i went to the stering colom lowered the stering wheel all of the way down and up again a couple of time in a fast and sturdy maner and the light's are working guess i'll keep a eye on thing's a while . mabey a wire was not making good conract ? just have to wait and see
thanks for all of the help.