Adding auto climate to XLT.
Looking at the wiring schematic, it looks like using the ODBII port is not an option since everything there goes through a gateway (aka. communication firewall) and the only lines present on that pinout are the Powertrain bus and the ABS bus. If it is the address difference, the only workaround would be to splice in a module in the harness somewhere to relay the messages. The real question now is where is the best spot to splice in the module. If the moderate-speed bus is used, the module could go under one of the seats or in the dash (likely near the gateway). If the high-speed bus is used, the module would have to be in the dash and would either be near the gateway next to the ODBII port or the behind the center controls bezel.
I saw a post on FB where someone had heard a auto climate panel from a 18 or 19 would work the heated seats in our XLTs without any kind of modifications, but I never heard confirmation of such.
Now I'll be following both that post and this to hopefully see something that works.
Now I'll be following both that post and this to hopefully see something that works.
Lurker
Joined: Aug 2019
Posts: 45
Likes: 33
From: Central IL
I saw a post on FB where someone had heard a auto climate panel from a 18 or 19 would work the heated seats in our XLTs without any kind of modifications, but I never heard confirmation of such.
Now I'll be following both that post and this to hopefully see something that works.
Now I'll be following both that post and this to hopefully see something that works.
Well that answers that...From what that guy had heard and was trying to get confirmation on was the 18 & 19 panels worked on 15 - 19 XLTs. But since you have personally tried one, I would believe you before I believed second hand info of what could be.
Junior Member
Joined: Nov 2019
Posts: 29
Likes: 82
From: Minnesota
I took a few minutes to look over all the wiring schematics (not just the controller) and I found out why the heated seat doesn’t work when you swap the bezel/controller out.
The updated bezel (from the Lariat with heated/cooled seats) sends information over the comms to the seat controller. The original bezel in the XLTs actual controls the seats directly (probably to reduce costs). Knowing this, the only realistic way to get the updated bezel working on the XLT is to make a module that directly ties in to the wires running into the seat. It will take a little more time to do this now because I have to read the messages and figure out the power management to the seat, but I still believe it’s possible to do at a reasonable cost.
The only other question I need to get answered before I start reverse-engineering the comms is if the connector/harness for the heated/cooled seat is under the seats in the XLT. I would prefer to be splicing wires on a part of the harness that is easily accessible and not being used than a part of the harness in the dash.
The updated bezel (from the Lariat with heated/cooled seats) sends information over the comms to the seat controller. The original bezel in the XLTs actual controls the seats directly (probably to reduce costs). Knowing this, the only realistic way to get the updated bezel working on the XLT is to make a module that directly ties in to the wires running into the seat. It will take a little more time to do this now because I have to read the messages and figure out the power management to the seat, but I still believe it’s possible to do at a reasonable cost.
The only other question I need to get answered before I start reverse-engineering the comms is if the connector/harness for the heated/cooled seat is under the seats in the XLT. I would prefer to be splicing wires on a part of the harness that is easily accessible and not being used than a part of the harness in the dash.
Junior Member
Joined: Nov 2019
Posts: 29
Likes: 82
From: Minnesota
I took a few minutes to look over all the wiring schematics (not just the controller) and I found out why the heated seat doesn’t work when you swap the bezel/controller out.
The updated bezel (from the Lariat with heated/cooled seats) sends information over the comms to the seat controller. The original bezel in the XLTs actual controls the seats directly (probably to reduce costs). Knowing this, the only realistic way to get the updated bezel working on the XLT is to make a module that directly ties in to the wires running into the seat. It will take a little more time to do this now because I have to read the messages and figure out the power management to the seat, but I still believe it’s possible to do at a reasonable cost.
The only other question I need to get answered before I start reverse-engineering the comms is if the connector/harness for the heated/cooled seat is under the seats in the XLT. I would prefer to be splicing wires on a part of the harness that is easily accessible and not being used than a part of the harness in the dash.
The updated bezel (from the Lariat with heated/cooled seats) sends information over the comms to the seat controller. The original bezel in the XLTs actual controls the seats directly (probably to reduce costs). Knowing this, the only realistic way to get the updated bezel working on the XLT is to make a module that directly ties in to the wires running into the seat. It will take a little more time to do this now because I have to read the messages and figure out the power management to the seat, but I still believe it’s possible to do at a reasonable cost.
The only other question I need to get answered before I start reverse-engineering the comms is if the connector/harness for the heated/cooled seat is under the seats in the XLT. I would prefer to be splicing wires on a part of the harness that is easily accessible and not being used than a part of the harness in the dash.
