Does anyone have some info on how the heated seats regulate their temp. When I first click on the heat they warm up fast then they seem to cool off. Do they they stay hot when there is no heat on in the cabin and when the heat in the cabin goes on they cool off? The manual offers no help.

 

I believe they are either on or off. I've never heard of a regulated heated seat. Most are either on or off, others are either Hi, Low, or off. I've also never known of a heated seat that is controlled or connected in any way to the cabin temp or heating/cooling systems. Typically, they either stay on or shut off after a certain period of time. If you feel like they are cooling off it is either because they shut off or you are just getting accustomed to the heat after a while.

 

I notice the same effect. My guess is they come on high and then drop to a lower temperature mode to prevent any chance of "burns" and lawsuits.

 

They sure come on strong and hot. It really tapers off to where it seems to be off. I will try to run them longer and see what happens. It really is not that cold yet so the true effect might not be felt.

 

I have some knowlage of heated seat operations, I worked as both a Ford and Jaguar tech. in the past. the seat heaters have timers, so after a few minutes they shut off (the same way the rear defrost grid works), also some have a temp. sensor to regulate the temp. and prevent them from turning on during hot weather. It has been a few years so my memeory is kinda vauge, however I do remember replaceing lots of them.

 

I am having the exact same problem... And I live up north were the temperatures have been getting into the teens at night. I was told that the problem was because my High Voltage battery was going bad (see another thread started by me!!). But after reading the reply's in this thread I kinda doubt that was the problem... I really doubt we are all having main battery failure's.

 

The seat heaters are going to work off the 12V system not the 330V system. Once the HV Bat gets the engine started the generator will be powering the system and stepping down to 12V. I can't think of a single reason why an HV battery failing would cause any symptoms in the seat heaters... It sounds pretty rediculous.

 

It seems when the heat is on in the cabin the heated seats go off much faster. If you run the heated seats only, they stay on much longer.

 

Not to bash the bad switch position anymore, but do the seats have their own fuse, where as I can remove it during the off season. It would be nice for pass. & me not to trip it this summer getting in.

 

Ken, I cannot be certain since I do not own heated seats, but I believe this to be true.

I have seen documentation that states:
"Do not tap accessories ( Radio, amp, CB, etc. ) into the heated seats circuit, as the heated seats already consume the maximum current allowed."

-John