[icspots]

Hello all. I finally got around to buying aftermarket carbon fiber seat heaters for my 3. Every year when it gets cold I think, "wow I should really put heated seats it, but it's way to fricking cold outside to be doing work". So this year I bought them when it's still nice enough outside to do stuff.

The heaters I bought each have a pre-wired harness and a 10a inline fuse. The instructions specifically state they each need a power supply which can deliver a constant 10a. Now I assume there's a little fudge factor in that power rating, and I also assume it would only have the maximum draw on the high setting. Still I'm wiring two of them so I'm trying to identify a good power source for them.

Looking at the fuse box of my '05 3s with cloth seats fuse F74 (IIRC) is a 20a circuit for seat warmers. My car doesn't have seat warmers, but I suppose it shares some of the wiring from the models of that year which had seat warmers.

My three questions for someone with a wiring diagram.

1)Is there anything else shared on that circuit, or can I safely put two heaters with potential 10a draws on a 20a fused circuit?

2)What wire in what harness do I need to tap in order to access that circuit? I realize I could use a fuse tap, but I'd rather just find the wire and solder my connections on. Also I don't have any taps of the correct size to fit those fuses and would need to order one.... whereas I have lots of solder and shrink wrap.

3)Each harness came with a non-connected inline 10a fuse/holder. Assuming I can use the OEM 20a circuit would it be safe to wire both heaters in parallel using just the 20a fuse, or should they absolutely have the 10a fuses installed for each 10a circuit?

Any help is appreciated.

 

[aeozyalcin]

You should keep the 10A fuses for each heater. Even though during a failure, your total current may not exceed 20A, the wire that is going to carry the current to the heater is probably only rated for 10A, thus a 10A fuse. Theoretically the worst case is that you could have 20A running through only one wire, and still not blow the main 20A fuse, and that would be dangerous. So keep the fuse.

 

[Cab0oze]

1) worst case, just try it and find out. If the fuse blows, you'll know
I suspect you'll be fine.
2) not sure what you're looking at, so no idea.
3) agree with aeozyalcin

 

[icspots]

As for 2) I'm wondering what wire in which bundle going to the PJB I could tap to access that 20a circuit. I'd rather just solder my connections for the two 10a inline fuses wired parallel than deal with fuse taps.

 

[aeozyalcin]

I don't know if this answers your question but you could also tap into the main unfused 12V (straight from the battery I believe) going into the fuse box, since you will have inline fuses for the seat warmers. Hope that helps.

 

[icspots]

I don't want them to be hot (tee hee) when the ignition is off. I might be able to remember to turn them off when I get out of the car except, A) I'd probably forget at some point, and B) I'm sure my wife would forget since her heated seats turn off with the car. I could redo the wiring harness they have and hook the signal wire for the relay up to the heater circuit and then pull off the battery, but I'd really prefer not to open the harness up and mess with it.

 

[aeozyalcin]

In that case, here is your best bet: look into how much current you can pull from the cigarette lighter. The power in the lighter is only available with key turned, so that is a plus. Honestly, those heaters take a lot of current, so the most current you can get will be through the lighter. Tap into the power lines going to the lighter.

Find out what fuse is on the lighter. If you find out that you can't pull enough current from there, honestly your only bet will be to lay wires straight from the battery with a relay that is controlled by the lighter. That way, you will still have power available only when ignition is turned on, and you won't be pulling excessive current from the factory harness, but you will be pulling it from the wires you ran from the battery. That is probably the safest way too.

Here is a diagram:

 

[myork]

I would think that all the necessary wiring is there, you just need to connect to it.
I dont think Mazda makes a different wiring harness for each model and option.

So for example if you go to the dealer and buy the OEM seat warmer switch assembly for the console (where the cig lighter and the passenger airbag light are), when you remove the existing panel, there are probably two connectors right there to plug in the switches.
Same would go for the seats, I am sure there is a harness tucked under the seat where the warmers plug in - you just have to find it.

So use the OEM switches and tap into the harness under the seats and you should be good to go.

 

[rdtk]

In that case, here is your best bet: look into how much current you can pull from the cigarette lighter.

In the 2008 sedan, fuse is 15amp. I dont think that would change for any other model. I would be surprised if it was 20 amp. I would think 15 amp would cover any requirement for that function.

But I only know my car, so I might be spit balling.

 

[rdtk]

Main Fuse Box for 2006

Internal Fuse Box for 2008

The blue fuse shown on the top row furthest to the left is the Cigarette lighter Fuse. Now that for sure!

I cant suggest anything. Not sure where you want to pull power from. I wouldn't want to pull a total of 20 amp's from any of the higher amp fuse locations.

I would pull power from 2 locations if I were you!

 

[upashi]

＞icspots

Sorry for fail to reply to your PM,, I sent e-mail but also just in case, dropping information here.


In PJB, top left larger blue connector, it's called J-03 connector.
At pin O, there is P/L (Pink with Blue) wire coming out IF you have seat warmer.

If you don't have seat warmer, wire may not be there.
By inserting 20A fuse into F74 seat warmer fuse location, J-03 connectors
pin AO P/Y(Pink with Yellow wire)-this is input side, and pin O-output for seat warmer should continue.

You can find appropriate size female terminal that fit size of pin O, J-03 connector and route wire for your seat warmer.


If not, splice power from this Pink with Yellow wire at pin AO, 20A inline fuse, then route to seat warmer will work safe as how it wired in those which has stock seat warmer.


If Pink with Blue wire isn't coming out from J-03 connector, it probably much easier to splice from Pink with Yellow wire of J-03 connector.

 

[icspots]

Well that's slightly different than the one on my '05. There's a fused spot on the bottom row marked for heated seats and rated to 20a. Mazda only included heated seats on cars with leather, but apparently wired for it to some extent.

Why would I want to pull 10a off of a 15a circuit for the lighter? Especially when I already have other things powered off of that circuit.

upashi was able to look up in wiring diagram for me and found this.

Exact wire for seat warmer is P/L (Pink with Blue stripe) wire that is coming out from
connector J-03 at pin O

Exactly what I needed. Now I can just tap that wire for my heaters.

 

[upashi]

Well that's slightly different than the one on my '05. There's a fused spot on the bottom row marked for heated seats and rated to 20a. Mazda only included heated seats on cars with leather, but apparently wired for it to some extent.

Why would I want to pull 10a off of a 15a circuit for the lighter? Especially when I already have other things powered off of that circuit.

upashi was able to look up in wiring diagram for me and found this.



Exactly what I needed. Now I can just tap that wire for my heaters.
[/FONT][/COLOR]

Does your car have Pink with Blue stripe wire at J-03?

If not, splice from Pink with Yellow stripe thicker wire at pin AO
make sure to fuse 20A this case. And you can split to power RH and LH both heater.
Also do sure use wire at least 16 or larger before split point(from splice point to split for RH and LH)

 

[aeozyalcin]

Why would I want to pull 10a off of a 15a circuit for the lighter? Especially when I already have other things powered off of that circuit.

I am glad you sorted it out. The diagram I drew with the relay would not be pulling the power from the cigarette lighter. The lighter would only click on the relay (<200mA) when the ignition is on. The main power for the heaters would be coming directly from the battery with the wire you ran.

But it seems like you found a more elegant solution so that's great!

 

[icspots]

I would think that all the necessary wiring is there, you just need to connect to it.
I dont think Mazda makes a different wiring harness for each model and option.

So for example if you go to the dealer and buy the OEM seat warmer switch assembly for the console (where the cig lighter and the passenger airbag light are), when you remove the existing panel, there are probably two connectors right there to plug in the switches.
Same would go for the seats, I am sure there is a harness tucked under the seat where the warmers plug in - you just have to find it.

So use the OEM switches and tap into the harness under the seats and you should be good to go.

In general it's true, however they tend to have a few different ones. Cars without NAV for instance have a different harness than ones which do. Since most cars with NAV had heated seats those connectors and wiring could be included with that harness. There are no extra plugs hiding behind the ashtray panel ready to plug up to the OEM switches. Getting that panel would be way more expensive than just using the switches which came with this, and besides I think the OEM are a single stage switch whereas my heaters are dual stage with a three position switch.

I am glad you sorted it out. The diagram I drew with the relay would not be pulling the power from the cigarette lighter. The lighter would only click on the relay (<200mA) when the ignition is on. The main power for the heaters would be coming directly from the battery with the wire you ran.

But it seems like you found a more elegant solution so that's great!

For some reason the diagram you included in your earlier post never displayed for me until today. Normally that's the way I would wire up a relay, however the one included in the harness had already been wired up with a jumper to just need power/ground and I didn't feel like hacking it apart.

As it turns out the PJB did not have the pink/blue wire at J-03 in the blue plug. The male half of the connection exists in the PJB, however there's no corresponding female side in the plug. If I'd had an appropriate connector I would have just added a wire to the plug, but I didn't and I didn't have an easy place to source one.

I ended up using the large pink/yellow wire upashi mentioned and spliced my two 10a inline fuses in parallel. Wires are run under the center console from there and down under the carpet on either side of the airbag module under the cupholders. The switches I mounted in the ashtray section between the airbag light and the lighter plug. The one annoying part was the instructions had clearly been printed prior to them changing the switch in the kit because it directed a 5/8" hole and it's actually a 3/4" switch. I had only drilled one so I only had to bore out the single hole. Still it was annoying.

The switches are easy to reach and look good. The blue accent light above them reflects very gently off of them at night so you can still see them even though the switches themselves aren't lit (the LED only comes on red/green depending on which setting you turn them to). I mounted them high of center because I'll eventually move my Max AC switch to below them from it's current home inside the ashtray area.

The heaters themselves are fantastic! The settings fall a little cooler and a little hotter than the ones in my wife's Prius (that only has a single stage). These things can get hot, and because of the carbon fiber elements they can stay hot instead of cycling on/off. I'm really happy with how they've turned out. Now I just wish I'd done it a few years ago. Also that I'd said F#$k it to the hog clips and just used zip ties to reconnect the cover on both seats. I tired of it after the first seat and the second went much much faster overall.

Here's the only picture I grabbed just showing how the switches look.

The heaters I used are these :arrow: http://www.amazon.com/gp/product/B005PJ334G/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

 

[Gobucs1981]

I just picked up leather seats I also got the switches from the junkyard they are from a 2112 Mazda 3 can anyone help with the wiring layout . I ran power to the seats they work but they on all time how does the switches work? The only have 4 wires two are for the lights on the switch can anyone help me with making a picture of how I should wire them. Seats have two wires for warmer anyway somehow I can get someone to make a drawing of how I should wire it please help