I tried to install my bottle heater today and it is not working, I thought i had it right but I guess not. Here is how I wired it, I mounted my relay in the trunk and ran the power to the battery, ran the red wire form the relay to the arming switch, blue to one of the wires on the bottle heater, the other wire on the heater i put to ground, grounded the arming switch and added the power wire. The switch lights up like it is supposed to but i am getting no heat, i am stumped any suggestions, I tested the bottle heater by putting to the + and - terminlas on the battery and it worked so i don't know whats up.

 

It is most likely your ground. Where did you ground it?

 

I had the same problem with mine for like 2 months. Finally, I took it all apart, wired it up on my kitchen floor and it worked. So, then I reinstalled it and it works now. I think that you may have a bad ground like I had. Are you tapping any wires for the ground, or are you grounding directly to the chassis. If you are grounding to the chassis, make sure that try to ground to an existing "ground" on the car, one that may have the paint taken off for best contact. If you try these, it may work.

 

I think you may be right, I wasnt to sure about the ground points I choose for this so I will try and redo them in the morning.

 

Sometime that themostate probe will go bad...