I'm working on retrofitting '14 Lincoln MKS 14 way power heated/cooled seats into a 2002 4Runner. I have all motors & lumbar wired. Had a Eureka moment on the TED and got it working!
3 position on/off/on rocker switch - hot/off//cold to: 5 pin 30 A relay - fan motor wired direct from relay with pigtails out to 8 pin DPDT relay to control hot/cold.
Fan is +/- in either on switch position. TED is +/- left, -/+ right.
However, no resistor, thermal control...
I tried wiring pot/var resistor to the out on DPDT to TED - only works 1 of 2 switch on positions (guessing other = -/-)
Would a dual potentiometer work? Would think it should and would wire in-between dual + out from 5 pin to dual in to DPDT. TOP /outer knob wired say +/-, bottom / inner knob wired -/+
Outer/top should only engage in say hot, inner/bottom only in cold.
Think I have it right but would love verification or simpler way if available.