Wiley
Does either light come on then quickly go out?
I had a similar problem and they had to replace the ground wire and add another one going to the control module. By the way, there is only one and its under the passenger seat.
Also, there is a TSB you could try first.
10/29/07
CLIMATE CONTROL SEAT FUNCTION
INOPERATIVE - NO COMMUNICATION - DCSM -
FORD:
2007-2008 Expedition
LINCOLN:
2007-2008 Navigator
ISSUE
Some 2007-2008 Expedition and Navigator vehicles built before 8/31/2007 and equipped with climate control seats may exhibit inoperative heating and/or cooling. There are no diagnostic trouble codes (DTCs) associated with this issue and IDS/PDS will not communicate with the dual climate control seat module (DCSM).
ACTION
Follow the Service Procedure steps to correct the condition.
SERVICE PROCEDURE
1. Turn the ignition switch to key on engine off (KOEO) position.
2. Run self test on DCSM.
a. If DTCs are present do not continue with this TSB, follow normal Workshop Manual (WSM) diagnostics for the DTCs.
b. If no communication with the DCSM, proceed to Step 3.
3. Remove power to the DCSM and wait a minimum of 2 minutes. This will reset the DCSM.
^ Expedition/Navigator - remove Fuse 8 in the battery junction box (BJB).
4. Reinstall the fuse(s) and recheck for communication.
a. If communication does not return, refer to WSM, Section 418-00.
b. If the communication is restored by resetting:
(1) Expedition/Navigator/- reprogram the DCSM to the latest calibration using IDS release 51.4 or later with patch 7. Calibration files may also be obtained at the website.
Also, check out this thread on the other site:
Driver side seat heater not working, 2010 Expedition - Ford Truck Enthusiasts Forums
Matt