2005 Ford Expedition Front Seats heater no work

seats
ford
expedition

#1

I guess it’s time to turn from a contributor to a questioner. It’s a 2005 Ford Expedition Eddie Bouer Edition with the heated/AC front seats. The seats have quit heating. I haven’t tried the AC option. Essentially, the push button control lights up for a second to two and then goes out. So it won’t heat. Bummer in winter. I found a technical service bulletin #18374 from Ford on this topic but I can’t get the full text. So can someone provide help?



I lost my job in January and haven’t found a new one yet so I kind of want info so I can do the repair myself if possible.



Thanks!


#2

Are you the sole driver or is there another one too?

Reason I ask is, if 2 different sized drivers use the vehicle the seats are constantly readjusted and this movement sometimes loosens or breaks the plug connections under the seat.

It’s possible the switch is faulty.

You can get the full TSB (#18374) summary at the NHTSA site by filling in the form.


#3

since you do see the power light come on; what you describe sounds like a bad wire or sensor which shutting prematurely and is shorting out, and turning it off.

there is a heat sensor (sorry i don’t know what its tech name is) that shuts the heater off when it comes up to temp. that should be under the seat too. that would be the first to check.

back when this worked, when you turn this on, do both seats heat, or is it just one per switch?


#4

It’s a one seat per switch. Both seats don’t work. I got a copy of the TSB from the Ford dealer (great to work with) and it references the control module for it. In some instances, the module can lose it’s connection and requires the connections to be reset. I haven’t had time to read it completely through. The fuses check out ok.

I’ll check the wiring underneath. I’ve had to diagnose electrical issues before so I know how to do it. It’s just a pain in the seat cushion. I’ll start with the simple stuff including reseating the control module. No fun, but should get it done.

Thanks!


#5

Have you checked/replaced the filters on each seat? If they are clogged, it would cause a quick shutdown. (That said, it is more likely to be the control module if both seats failed at the same time.)


#6

Please note that there is a lot more to it than that. There is an electric/electronic heat/cool module, and dual blower, and some sensors under each seat.