View Full Version : Looking for a circuit
The goal is to connect my seat heaters to a switched power source. Sounds easy enough, right?
Here's the challenge: I'm using the heater circuit for..... the heater. I have a radio circuit, but that's 10 Amps. Is that enough? I might have the yellow wire from the Coyote pigtail (C160A), but that's 10A as well.
I could tap into the master cutoff, but I would prefer something switched from the ignition key. I'm looking at the RF schematic as I write this, but I'm not coming up with any creative ideas. That's where you come in. Any recommendations for where I can tap in to for seat heater power?
https://thefactoryfiveforum.com/attachment.php?attachmentid=100078&d=1546550396
Richard Oben
01-03-2019, 04:55 PM
I pulled an additional wire off of the ignition switch, then with the supplied fuse holders powered the seat heaters. The harness should but does not have any "extra" circuits. JMHO. Richard.
edwardb
01-03-2019, 05:22 PM
I'll suggest what I'm doing with my Coupe build. I too ran out of circuits. It's pretty typical to use the RF Orange EFI or Coil wire for the Coyote ignition sense wire. That's what I've personally always recommended and did on #8674. But it's overkill. It's a large gauge wire and a 15 amp circuit. Easily enough for the heated seats. So that's what I'm using it for on my Coupe build. I'm using the tan electric choke wire for the Coyote ignition sense wire.
Tan electric choke wire! I'll go look for it. Heaven knows where that got tucked away... Thanks, Paul!
CraigS
01-04-2019, 07:51 AM
Re-read EdwardBs post. The RF Orange EFI or Coil wire for the seat heaters.
phileas_fogg
01-04-2019, 08:30 AM
I'm using the 10A choke circuit for my seat heaters with no problems. Got the idea from QSL, who used the 10A radio circuit for his seat heaters.
John
Re-read EdwardBs post. The RF Orange EFI or Coil wire for the seat heaters.
Yes - I understood that. My comment referred to the concept of using the tan choke wire to replace the EFI/Crank wire for ignition. The radio circuit was one of my original questions. I questioned whether 10 Amps would be sufficient. Sounds like it works for Phileas.
edwardb
01-04-2019, 10:12 AM
Yes - I understood that. My comment referred to the concept of using the tan choke wire to replace the EFI/Crank wire for ignition. The radio circuit was one of my original questions. I questioned whether 10 Amps would be sufficient. Sounds like it works for Phileas.
Probably 10 amps for the seat heaters is OK. But the 15 amp EFI/Crank wire provides more margin and is way more than the Coyote ignition sense circuit needs. It's an easy change. Actually, the Coyote ignition sense could go to just about any ignition switch powered circuit. It draws little/no current, evidenced in part by the very small gauge wires Ford has in the harness for it. It's just a +12V signal to the PCM to wake up and stay on.
FLPBFoot
01-04-2019, 11:25 AM
I'm using the 10A choke circuit for my seat heaters with no problems. Got the idea from QSL, who used the 10A radio circuit for his seat heaters.
John
Yep, same here. Using the Elec Choke circuit for my seat heaters.
Ducky2009
01-04-2019, 11:48 AM
Use the empty fuse slots in the chassis fuse box. With the Coyote, the choke and fuel pump fuses are not use (along with the fan). I used a scalpel to scrape the old words (choke & fuel pump) off and a gray sharpie fine tip marker to write seat heater. The choke is a 10A and fuel pump is 15A. Make sure you use the 10A fuses supplied with the seat heaters. I used two fuse slots, one for each seat heater.
EDITED: I did not use the in-line fuse and the fuse box fuse. Also, My seat heaters called for 10 Amp. Is yours 10 or 15 amp?
phileas_fogg
01-05-2019, 10:28 AM
Use the empty fuse slots in the chassis fuse box. With the Coyote, the choke and fuel pump fuses are not use (along with the fan). I used a scalpel to scrape the old words (choke & fuel pump) off and a gray sharpie fine tip marker to write seat heater. The choke is a 10A and fuel pump is 15A. Make sure you use the 10A fuses supplied with the seat heaters. I used both, one for each seat heater.
Excellent point; like Ducky, I kept the in-line fuse to each seat heater.
John
OK, last question on this topic: heating elements are installed in the seats. Element wires can exit the seat at the inside or the rear of the seat. I can place the wiring components directly behind the seat. Last part: run the wires through an opening in the transmission tunnel inside of the tunnel to the dash. Take a look at the photo:
https://thefactoryfiveforum.com/attachment.php?attachmentid=100812&d=1547690616
The question is shall I run the wires through a hole forward or aft of the seat belt connection? I'm just trying to avoid any contention with other components. Thanks!
OK, last question on this topic: heating elements are installed in the seats. Element wires can exit the seat at the inside or the rear of the seat. I can place the wiring components directly behind the seat. Last part: run the wires through an opening in the transmission tunnel inside of the tunnel to the dash. Take a look at the photo:
https://thefactoryfiveforum.com/attachment.php?attachmentid=100812&d=1547690616
The question is shall I run the wires through a hole forward or aft of the seat belt connection? I'm just trying to avoid any contention with other components. Thanks!
I ran mine about 2-1/2 to 3" forward of the seat belt tab. My switches are in the trans tunnel cover. I ran the power wires along the floor inside the passenger compartment and up behind the dash. With the carpet installed, everything is hidden except for the wires going into the tunnel, which with the seats installed are not seen.
https://thefactoryfiveforum.com/attachment.php?attachmentid=84726&d=1524445668
https://thefactoryfiveforum.com/attachment.php?attachmentid=84729&d=1524445690
https://thefactoryfiveforum.com/attachment.php?attachmentid=84723&d=1524445389
https://thefactoryfiveforum.com/attachment.php?attachmentid=95884&d=1540081011
Ducky2009
01-16-2019, 10:46 PM
I ran the wires out behind the seats because I have a seat adjuster on the DS and spacers on the PS to keep the seats the same height. The wires are in the corner where the floor and tunnel side meet and up in the front corner where the tunnel meets the foot boxes. They are taped down in place with aluminum 2" tape.... thinking it would be hard to damage the wires in the corner and the aluminum tape is pretty durable stuff. After taping the wires, I installed the Dynamat last, adding more protection to the wires. Sorry, no pics
The switches are mounted in the dash.
100818
phileas_fogg
01-17-2019, 08:09 AM
I ran my wires under the carpet along the inside corner of the floor aluminum, then up under the carpet of the transmission horseshoe and under the dash. My switches are on the under dash panel, and the plug ins for the seats are just in front of the seat belt attachment point.
John
https://farm5.staticflickr.com/4481/37941146946_c86250a37d_k.jpg (https://flic.kr/p/ZNJi8Y)IMG_4178 (https://flic.kr/p/ZNJi8Y) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr
boat737
01-17-2019, 09:29 AM
Ran the wires in on that angled panel at the rear, near the junction with the trans tunnel. I have sliders, so left enough slack behind the seat for movement. Lots of room on the back side, away from the transmission and drive train.
Lots of great ideas here! I'm mounting the switches on the trans tunnel, except I made a plate out of aluminum to mount them on that will be forward of the shifter. John - it looks like you covered the entire bottom of your dashboard and mounted a vent in that piece. That would solve a different problem for me, so thanks for that idea, too!
phileas_fogg
01-17-2019, 10:57 AM
The under dash is actually three panels, 'cuz that's the size aluminum I had on hand.
Don't use the headlight switch bracket to determine the depth (between the 2" frame & the dash itself) of the under dash; instead, make the depth such that the top of the dash is flush to the 3/4" arc. I didn't, so the dash at the bottom of the arc is slightly pulled away from flush (since I hid the dash fasteners with brackets under the arc it didn't matter for me).
I drilled & tapped the 2" frame for #10-32 screws to secure the tab for the under dash, and used #10-32 riv-nuts on the tab for the dash itself.
John
https://farm5.staticflickr.com/4329/36123021622_d2545be019_k.jpg (https://flic.kr/p/X34VPC)IMG_3470 (https://flic.kr/p/X34VPC) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr