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My girlfriend has a 2016 Subaru Legacy and I got in over my head on replacing her seats with leather seats out of an older generation legacy.
Long story short I installed 2013 Seats in her 2016 and rewired everything to work except the seat heat has me baffled. At this point I've already ordered aftermarket pads and I plan to take the leather off and install them but I still have some questions..
The difference between the 2016 and the 2013 is one is a 3-wire setup,the other is a 4-wire setup. And I don't know the history on the seats I installed so it's quite possible the seat heat doesn't work at all on them. I was able to get the passenger heat to turn on but my issue I can't get either of them to work on the switch
What I'm seeing in the 4 wire connector from the harness:
Yellow wire has constant 12v+ with key on
White wire has 5v key on
Black is ground
Blue also appears to be ground
The heat switch has three settings, high medium low (and off). The buttons appear to work fine and the seat heat worked fine in the old seats (which I now regret burning them in a bonfire). But testing the powers and the grounds nothing changed regardless of the switch positions. I bought the alldata schematics for both the 2013 and 2016 and learned that disconnecting the battery can reset the heat control module (which I still have not located by the way).
So I did that today and it did change something. When I reconnected the battery now I have resistance between the black and the car ground. So I think I have figured out that the ground resistance perhaps is controlled by the heat switches. Except I cant get the ohms to change. Perhaps without a thermoresistor connected it will not turn on the heat? To word this differently, before the black was continuous (0 resistance) to ground, and the heat turned on regardless of the switch position. Now that I've reset it, there is a lot of resistance on the black and i have the connector under the seat disconnected and I'm toggling the seat heat and nothing is changing. I think it would only change perhaps if it was connected to the thermoresistor
Anyway my hope is I can use the factory switches, leave them in place to control my aftermarket heat pads. However I'm beginning to suspect that will be difficult if my understanding is correct on how the switches currently function with the controller
Any thoughts or experience?
Specifically,
1: Where is the heat control module on a 2016 legacy?
2: Can I wire a thermoresistor and use the 2013 seat heaters that are currently on the seats somehow (4 wire from harness, 3 wire to older heat pads).
3. Can anyone confirm for me if the seat heat is controlled by adjusting the resistance on the ground circuit?
Thank you!
Long story short I installed 2013 Seats in her 2016 and rewired everything to work except the seat heat has me baffled. At this point I've already ordered aftermarket pads and I plan to take the leather off and install them but I still have some questions..
The difference between the 2016 and the 2013 is one is a 3-wire setup,the other is a 4-wire setup. And I don't know the history on the seats I installed so it's quite possible the seat heat doesn't work at all on them. I was able to get the passenger heat to turn on but my issue I can't get either of them to work on the switch
What I'm seeing in the 4 wire connector from the harness:
Yellow wire has constant 12v+ with key on
White wire has 5v key on
Black is ground
Blue also appears to be ground
The heat switch has three settings, high medium low (and off). The buttons appear to work fine and the seat heat worked fine in the old seats (which I now regret burning them in a bonfire). But testing the powers and the grounds nothing changed regardless of the switch positions. I bought the alldata schematics for both the 2013 and 2016 and learned that disconnecting the battery can reset the heat control module (which I still have not located by the way).
So I did that today and it did change something. When I reconnected the battery now I have resistance between the black and the car ground. So I think I have figured out that the ground resistance perhaps is controlled by the heat switches. Except I cant get the ohms to change. Perhaps without a thermoresistor connected it will not turn on the heat? To word this differently, before the black was continuous (0 resistance) to ground, and the heat turned on regardless of the switch position. Now that I've reset it, there is a lot of resistance on the black and i have the connector under the seat disconnected and I'm toggling the seat heat and nothing is changing. I think it would only change perhaps if it was connected to the thermoresistor
Anyway my hope is I can use the factory switches, leave them in place to control my aftermarket heat pads. However I'm beginning to suspect that will be difficult if my understanding is correct on how the switches currently function with the controller
Any thoughts or experience?
Specifically,
1: Where is the heat control module on a 2016 legacy?
2: Can I wire a thermoresistor and use the 2013 seat heaters that are currently on the seats somehow (4 wire from harness, 3 wire to older heat pads).
3. Can anyone confirm for me if the seat heat is controlled by adjusting the resistance on the ground circuit?
Thank you!
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