5th Gen Seats into a 4th Gen?

[Ramman2]

Honestly, I've essentially given up on the cooled seats.

The 4th gen HSM uses a two wire system for the fans, and adjusts voltage for speed, i.e. 8v for low, 12v for high.

The 5th gen cooling fan motors use a three wire system, constant 12vdc, ground, and a PWM speed control.

So, I can either swap in 4th gen seat cooling motors (good luck finding those at reasonable prices), find a universal fan motor that bolts up (unlikely); or find an alternate control system for the 5th gen cooling fan motors (something like a universal PWM controller, but I tried one and wasn't smart enough to figure it out).

Supposedly, somehow in the TCM-2800 (I'm running Russel's 8HP70 swap kit in my '12 Ram, and ditched the 545RFE), I can also program PWM outputs. But again, I'm not really saavy enough to figure it out - there isn't a lot of info out there on it; and I'm not motivated enough to figure it out on my own vs. other projects.

It would be nice to have, but in Ohio, it's not a super important option.

Thanks for the reply. I’ll probably pass on trying to get it to work as well but if I do end up getting them to work I’ll definitely let y’all know

 

[JohnVill]

I just wanted to give an update on my build w/ 5th Gen 1500 Laramie Longhorn interior. I was able to get the seats in with power, but I’m still trying to find any solution for the heated/cooled function to work. I also have the center console fully installed and the door panels from a 5th Gen 2500 was a direct fit.

 

[emjohn4]

So, I got the cooled seats working.

I used a PWM controller to make it work. The output from the 4th gen HSM goes to the PWM controller, and the output of the PWM controller goes to the 5th gen fans.

I had to wire the fans directly to the PWM controller - since in the 5th gen, the fans have constant +12vdc when the ignition is on.

So, it's now 100% functional!

 

[emjohn4]

I just wanted to give an update on my build w/ 5th Gen 1500 Laramie Longhorn interior. I was able to get the seats in with power, but I’m still trying to find any solution for the heated/cooled function to work. I also have the center console fully installed and the door panels from a 5th Gen 2500 was a direct fit.
View attachment 534418

Tell me about that Radio you've got....

 

[JohnVill]

Tell me about that Radio you've got....

Yeah, it’s just a Linkswell T-Style radio but I programmed the start up and load up screen to the Laramie Longhorn Logo. If you any more questions I’d be happy to answer them.

Could you tell me everything I would need to get to try and get the cooled seats working?

 

[emjohn4]

I assume the same HSM is in the '13+ trucks as was the '09-'12 trucks....

I added pictures to my prior post. Basically, the outputs of the 4th gen HSM are ~+10vdc (low) and ~+12vdc (high).

Take those outputs to the input of a PWM controller.

On the 5th gen fans, cut the wire to the fan on the seat side. The red is +12vdc, the black is ground, and the white is the PWM control. Wire the +12vdc and ground to the same inputs as the PWM controller. The PWM output gets wired to the white wire on the fan motor.

That's it! When you turn on the cooled fans, the PWM controller and fan gets +12vdc. That's your high speed. When you push the button for the low speed, the fans will then get ~+10vdc.

 

[emjohn4]

I assume the same HSM is in the '13+ trucks as was the '09-'12 trucks....

I added pictures to my prior post. Basically, the outputs of the 4th gen HSM are ~+10vdc (low) and ~+12vdc (high).

Take those outputs to the input of a PWM controller.

On the 5th gen fans, cut the wire to the fan on the seat side. The red is +12vdc, the black is ground, and the white is the PWM control. Wire the +12vdc and ground to the same inputs as the PWM controller. The PWM output gets wired to the white wire on the fan motor.

That's it! When you turn on the cooled fans, the PWM controller and fan gets +12vdc. That's your high speed. When you push the button for the low speed, the fans will then get ~+10vdc.

This is the PWM controller I bought, FWIW. There are many on ebay that appear to be similar...but I can state this one works.

Signal Generator Module Adjustable PWM Pulse Frequency Duty Cycle Square Wave GL | eBay

LCD display frequency and duty cycle, very clear, PWM output can be set to the frequency and duty cycle;. PWM output, you can set the frequency, duty cycle;. *** (no decimal point): the smallest unit is 1Hz, the value range of 1Hz ~ 999Hz;.

www.ebay.com

 

[Nicksurla]

A few pieces of info:

1.) The seat belt buckles on the 5th gens physcially work with the 4th gen seat belts, but do not remove the seat belt light. The fix - swap in the 4th gen seat belt buckles. The plug on the 5th gen seats are exactly the same.

2.) The airbags on the 5th gen seats work for the 4th gen SRS system. The plug needs re-pinned (i.e. remove the wires from the 5th gen connector and place in appropriate section on the 4th gen connector).

3.) The 5th gen seats have the HSM under the passenger seat. The 4th gen has the HSM under the drivers seat. I am going to use, in effect, the 4th gen HSM and logic, and connect to the seat heaters / coolers on the 5th gen. This will be a longer, slower process - as my truck did not have heated / cooled seats originally.

4.) 5th gen rear seats (top) vs. 4th gen rear seat (lower ) brackets:


View attachment 195616

How does the wiring harness look now

 

[kstill]

Those look awesome!! I wish I had the money to update my truck like this.

 

[Nicksurla]

Hey new to the forum here so I hope I’m doing this right.
I also bought a set of 5th gen 1500 seats to put in my 4th gen 1500. I’m getting a little snagged up on how to switch the brackets over. Did you switch them over or modify the 5th gens or what? Pictures would be great if you have them. Thanks

I just did mine I cut the legs off the 5th gen an drilled out the rivets on the 4th then put the 4gens legs back in there spots

 

[Ktaylor_j]

Unreal.

 

[ricky_bobby]

Excellent to hear you got them working although its much more work than I would have time to take on - the swap from Sport to Limited seats was enough for me ha!

 

[dhulsey779]

I just wanted to give an update on my build w/ 5th Gen 1500 Laramie Longhorn interior. I was able to get the seats in with power, but I’m still trying to find any solution for the heated/cooled function to work. I also have the center console fully installed and the door panels from a 5th Gen 2500 was a direct fit.
View attachment 534418

Was the console a direct bolt in or was there some modifications made?

 

[Ashton]

Congrats on getting all working! Must feel great to have it all finished! I've been trying find a HD 5th gen passenger seat to put into my 4th gen truck with manual sport heated seat on the passenger side. Driver is power. I don't want to have cooled seats or anything like that. I was going to just swap my wiring and upholstery on a power frame but not sure how the motors wire up. Would anyone have a pin out for the HD 5th gen or 1500 5th gen if they use the same connectors.

 

[Bjames61]

I am a little confused on the wiring for PWM and HSM anyway you could draw a diagram for the witing?

 

[Cool_Hand_Luke]

@emjohn4 I sent you PM

 

[itswiggs]

Did you by chance hook up position 9,10 or 19 on the drivers side (connector xy410) or position 22 on passenger side (connector xy420) from the 5th gen seats?

I had messaged you @emjohn4 but wanted to get in this thread to see if you plus anyone else might have insight. I swapped everything to the 5th gen connector and eliminated the 4th gen ones.

I had to add the steering wheel feed, can ihs and can c, courtesy lamp, and the power wiring from the pdc (still have to wire memory features if I end up going that route) I read the 4th gen hsm was the one used. I am just trying to give the plug everything it’s asking for and hopefully The 5th gen hsm will work?

Additionally, the switch block is on its way for the heated/ventilated seats and heated steering wheel. Do I need to have any wiring running from the seats back to the plug on block? From what Im seeing and reading in this thread I don’t think I do. I just want to confirm.

 

[emjohn4]

Did you by chance hook up position 9,10 or 19 on the drivers side (connector xy410) or position 22 on passenger side (connector xy420) from the 5th gen seats?

I had messaged you @emjohn4 but wanted to get in this thread to see if you plus anyone else might have insight. I swapped everything to the 5th gen connector and eliminated the 4th gen ones.

I had to add the steering wheel feed, can ihs and can c, courtesy lamp, and the power wiring from the pdc (still have to wire memory features if I end up going that route) I read the 4th gen hsm was the one used. I am just trying to give the plug everything it’s asking for and hopefully The 5th gen hsm will work?

Additionally, the switch block is on its way for the heated/ventilated seats and heated steering wheel. Do I need to have any wiring running from the seats back to the plug on block? From what Im seeing and reading in this thread I don’t think I do. I just want to confirm.
View attachment 561872View attachment 561873

Nope, I did not connect any of the position sensor wiring....mainly because my 2012 didn't have those items (not sure if it is memory seating position or for the airbags to adjust based on seat position).

Since my 4th gen is 'pretty old' in automotive terms, I'm not 100% sure what enhancements have been made in the 4th gen classics in the recent years.

 

[emjohn4]

I ended up using the 4th gen connectors on the 5th gen seats.

Here's the really tricky part (and I haven't finished it yet - found a new toy to distract me). The 4th gen seats...had the HSM below the drivers seat. The 5th gen seats, had the HSM below the passenger seat. So I took the 5th gen PASSENGER seat harness off, moved it to the DRIVERS seat, and moved the drivers seat harness to the passenger seat. That way...the 5th gen seats 'mimicked' the 4th gen setup (with the HSM on the DRIVERS side). When you do this, the seat fore/aft power motor connectors needs repinned to reverse the polarity, the others are fine. If you don't do this, nothing bad happens, just 'front' means the seat moves 'back' and vice versa.

PS: DT is the model designation for the 5th gen.

Attached is a pdf of the excel file (it is a work in progress). PM me your email andress and I will send the excel file. The airbags in the 5th gen connect just fine to the 4th gen computer, you just have to repin the connector. I have full functionality of the 5th gen seats, and have stalled with the passenger side heat (drivers is hooked up, passenger didn't pay for the truck anyhow), and ventilation on both sides. Like I said, new distraction...


View attachment 216042

It's funny...the truck is still in it's spot, and quite a few more miles on it than when I took this pic....without looking at the fuel log book, I'd guess from memory that the truck had about 70k miles on it in this pic.

The Porsche is gone - sold in the fall of 2024. Toys come and toys go. Truck in the below pic sitting at 136k miles.

 

[itswiggs]

@emjohn4 I just wanted to say thank you for this thread and being quick to respond.

I just tried the seats tonight. I still have to work on the brackets. And some wiring. Long story short, the seats work both heated and ventilated. Oh man I can’t believe it. The only issue I’m having now is my “hard buttons” are not working to turn them on and off, but the soft keys are present on the radio(I’m thinking it’s one of the settings in alpha). Other thing is the airbag system. I think I have to figure out the passenger occupant sensor return as well as install the seat belts themselves.

I really was hesitant about this. But now am so excited and ready to get on with the center console and rear seats. I think out of everything I’m so surprised the 5th gen modules worked. What a relief. I will post updates on progress.

if anyone wants wiring and pin out info I can give you what I did and where I sourced the connectors.