Mirror heat wiring

[Firepuppy]

Hi Everyone im new to this site but have been on Ford Truck World for awhile so i hope you can help me i inquired a set of Muth Signal Mirrir with Heat for my 99 Expo and i was wondering seeings the muth heat timer is so expensive how can i wire the mirror heat up myself i was told i could use a relay and do it that way but i dont know how to wire the relay for that can some one help me i have had the mirrors in my truck for 2 years now and i do have the wires run for the heat already andwinter is coming in Upstate New York
thanks Everyone

 

[ELVATO]

Do you have rear (liftgate) window defrost? On the 03-06, the heated mirrors run off of that. If yours is the same, the rear defrost would turn off automatically, which would then turn off the mirror heaters automatically.

You'd just need to wire a relay that uses the rear defrost as the trigger. When you say you have the wires run, what do you mean?

 

[Firepuppy]

Mirror heat

ELVATO
Thanks for your reply well you have a point i never thought of that what i mean by i have the wires run is from the mirrors into the compartment under the dash just sitting there waiting to be hooked up Now how would i hook them up to the rear defrost (yes mine does have rear defrost) with a relay