heated seat fault

[DTi Elite]

the heated drivers seat in my elite is not working , just after any info anybody may have , the switch lights up & I have identified a live feed to the seat when the switch is on , this live feed is in a plug of 5 wires .
what I am wondering is if there is supposed to be a feed back to the switch in order to control the thermostat , I have no wiring diagram at present but could really do with a bit of info .

[DTi Elite]

worked it out for myself in the end as even autodata had no wiring diagram , took the seat out & stripped it , using a battery charger , test light & multimeter I found out the bottom heater pad was open circuit , did a bit of tracing on the heater pad & narrowed the fault down to a 2 inch section of wiring , soldered a bypass wire across it , rebuilt the seat & hey presto it works a treat