I have a 99 F150 with out auto on-off switch. Can I replace with auto on-off switch.

Thanks
IRV

 

Yes, you can replace the switch if thats what you are needing to do. But adding a switch with the autolamp feature will not give you the autolamp functionality, provided the truck wasnt already autolamp eqquiped. In my case, my switch has 2 plugs, one large rectangle with 2 rows of pins, 6 on the top and 4 blanks on the bottom, evenly spaced, and the second plug is a 4 pin rectangle. The autolamp switch I ended up with has (rather, would have) the autolamp function by turning the switch all the way to the left.

There is an older Ford version where Autolamp is acheived with a roller switch (i cant think a better term) that is next to/just like the instrument panel dimmer.

I have a 2001, so my wiring harness is likely different from yours. But yes, I have an autolamp switch with no autolamp benefit and my lights work just fine. HTH. My reason for my switch swap was to add fog lamps.