E39 heated rear seats retrofit project.
Winter is coming.
The plan is to fit seat heating pads to rear bench and backrest and add 3 stage switch, similar to the one for front seats, to control it.
So far i have found only 2 similar projects from the net. One was with e38 dial type switches and second had 2 stage switches from x5.
My plan is to butcher one switch centre and try to combine it with rear cup holder or cubbyhole.
I have ordered 2 sets of pads. When they arrive, i will measure the power they draw and temperatures and go from there.
It could be a very slow project, so bear with me.
Examples from net.
http://images52.fotki.com/v637/photo...IMG1397-vi.jpg
http://farm3.static.flickr.com/2446/...348aa68530.jpg
PS. No one ever sits in the rear of my car :cool:
RE: E39 heated rear seats retrofit project.
Fairplay to you. Great project to undertake, looking forward to your slow updates.
Re: E39 heated rear seats retrofit project.
Very nice love this car and it just keeps getting better
Another option for you is this
http://img.tapatalk.com/d/14/09/30/a8ehemu8.jpg
Theres also another with an aux port in the middle
RE: E39 heated rear seats retrofit project.
I like this one. I may go the x5 button route afterall.
E39 heated rear seats retrofit project.
One of the lads in work has it on his E60 along with a heated steering wheel, very cool (heated :D) option
RE: E39 heated rear seats retrofit project.
Heating pads arrived today. I measured resistance and came up with three power settings.
Stage 1:
U=12v
R=11.3 ohm
I=1.06A
P=17.7W
Wiring diagram for stage 1
https://lh5.googleusercontent.com/-_.../stage%2B1.jpg
Stage 2:
U=12v
R=7 ohm
I=1.7A
P=20W
Wiring diagram for stage 2. Resistor 4 ohm, minimum 25w, 40w recommended.
https://lh5.googleusercontent.com/-0.../stage%2B2.jpg
Stage 3:
U=12v
R=3 ohm
I=4A
P=48W
Wiring diagram for stage 3.
https://lh6.googleusercontent.com/-C.../stage%2B3.jpg
Sorry for my bad MS Paint skills :D
RE: E39 heated rear seats retrofit project.
Put all 3 stages to test today. Stage 1 & 3 are good. Stage 2 is no go. Resistor gets too hot for my liking. So back to drawing board with stage 2.
RE: E39 heated rear seats retrofit project.
Great project ! How are you going to wire it ? ie how is the link used in stage 3 not going to effect stage 1.
The easiest way I see it involves lots of relays I'm curious about how your going to do it .
About the 3 stage switch if you have it on its highest/hottest setting are the other 2 (low & medium) contacts made ?
Edit: I see you don't have the switches yet
RE: E39 heated rear seats retrofit project.
I will use relays to switch between stages, so that when stage 3 is in effect, stage 1 and 2 are disconnected from the pads. Plan is to use arduino to control the relays.
RE: E39 heated rear seats retrofit project.
New idea for stage 2.
Values or r2 and r3 will define current. I use potentiometer in place of r1 and r2 to get the desired temperature and replace it later with correct resistors.
https://lh5.googleusercontent.com/-z...Bregulator.jpg
I hope this works. :D