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Relay trigger power

Hello all. The truck is a 2017 RCSB, 5.0. I have the 12V Systems remote start kit primarily to keep the dog hot or cool when the truck is parked while I run quick errands. I am now in Minnesota for the week and I realized that my aftermarket ComfortAir seatheaters do not activate with remote start while the heater does. It has been so long since I have been up here that I forgot about frozen seat syndrome. It is like desert seat syndrome but cold. Oh so very cold. Does anyone know of a fuse in the engine compartment fuse box that goes hot when the 12V System remote start kit is activated. I run all my additional circuits direct from B+ through relays triggered by the wiper moisture sensor circuit, not an option on my truck. This circuit is ignition on active so it triggers my 3 relays fine but I want the seatheaters to come on with the remote start. If you can help me find a fuse that goes hot with my remote start I can make the change while I am here. Otherwise, I will have to wait until I get home to go circuit chasing.

I found a good portion of the engine fuse box that hots up with the remote start and ignition run. The fuses start at 93 and run to, I think, 112. Do not pick the fuse designated as voltage control it is near the top, 109 or 111. If you use an aftermarket fuse tap you will see the voltage to the battery skyrocket. I was wondering what was going on when it reached 20V and immediately shut the truck off. Changed to a single use fuse in the 90's and all is good. My small inverter, if left on, and seat heaters now fire up with the remote start and stay on when I turn the ignition to run. I will go pull my manual and give more exact information if anyone wants it.

Very interesting. Good to know.

I'm more interested as to the why it shot up to 20 volts on the voltage control fusees.

Been gone for awhile but determined the high voltage issue on start up. It is not an issue. The engineers decided that with the loads from the starter and other devices that hit immediately and the in 2017 option for Stop N Start, later to become mandatory, they needed to boost charging voltage for a short period immediately after start up. In approximately a minute the voltage drops to a normal 13.2+. My thought is that the time span for the increased voltage is extended based on battery initial voltage, temp, etc. All the things that drop voltage on initial start up.