Seat Swap: 2023 Bolt EV 2LT to 2017 Volt seat

Seat height is about the same. If anything, the Volt seat is the TINIEST bit lower. I only say that because my leg gets caught on the seat less getting in and out than it does on the Bolt seat.

I'm trying to figure out the best way to physically hold the wires in the connector. On the seat side, the salvage yard just cut off the cable, so I have the connector that matches the seat, although it only had very short wires on it. At least there was barely enough to solder some longer wires to it.

I do NOT have a matching connector which would plug in to the car. I DO have the right size single-wire terminals which are appropriate to go to the individual pins in that connector. So, I now have a perfectly good pig-tail going from the seat to the car body EXCEPT that there isn't much physically holding those pins in.

SO, I'm trying to figure out the best way to do that.
After thinking about what I have for skills and resources, some sort of "cast-in-place" filler material would be great. A friend was recently using hot-glue in a project as "poor-man's acrylic". I decided to make a test piece.

I have some generic automotive connectors and wired one up with 3 wires to it. Then I crimped matching bare terminals on another three wires and just plugged them in - but NOT in a matching housing - just the wires hanging there. Next, I wrapped some masking tape around the electrical connector and shot some silicone lubricant spray inside it to act as a release agent. Then I warmed up my hot glue gun and gobbed a generous amount into the connector.

After it had cooled, I pulled off the masking tape, trimmed off the extra glue, slid a knife blade between the glue and housing, wiggled and fanagled it a bit, and finally got it to pull cleanly free. The connections are good and the hot glue is a perfect shape matching the mated housing. I can plug and unplug it easily. It even makes a nice POP vacuum noise when I pull the connectors apart.

Based on this, I think that simply using hot glue would be a perfectly acceptable way to hold the wiring in place.

Also, man am I sick of all the negative comments!
On social media, I have gotten HUNDREDS of comments about this. For the most part, it's also hundreds of Thumbs-up, but 9 out of ten comments are some variation on "but the air-bags!!!!". One person was convinced that swapping the seat would void the warranty on the entire car. Another person is convinced that building a pig-tail is going to randomly cause the air-bag to fire.
People never even read the comments that are already there, they just keep repeating negative, ignorant thoughts.

I have had a handful of private messages and the like sent to me saying something along the lines of "Thanks for doing this", "You're a pioneer", etc.
Those are the people I do this for!!!

The heated seat isn't working. At least on the driver's side - the 2017 Volt seat.
After doing some research, both of the front seats are controlled by a "Seat Heater Module" which is mounted under the passenger seat. So, for example, if I simply removed the passenger seat, the driver seat would no longer be heated.

The Seat Heater Module appears identical between the 2017 Volt and the 2023 Bolt, but it IS a different part number. Not sure exactly what the difference is, I would imagine it's probably some minor difference in the software/firmware. But it's just enough that the Volt seat heater comes on and stays on full blast, and can't be controlled with the Bolt's seat heater button.

The passenger seat heat still works fine.

I wonder if I also swapped in a passenger seat from a Gen 2 Volt (with the Heater Control Module mounted under it) if the heat would then work with both seats, or if it would still be incompatible with the switches in the Bolt.

For now, I simply disconnected pin #1, which carries the 12V+ power for the seat heater. I would think that I could actually just rig up a manual POWER switch on that wire to make a simple FULL-ON/FULL-OFF for the heat on the driver seat, although that would certainly be inelegant compared to still using the Hi/Med/Lo switch built in to the car.

JimBolt said:

Do you have a Volt handy you could check the signals coming from it's module...

Click to expand...

My sister has a Gen 2 Volt, but I'm not sure exactly what I'd be looking for. According to the data I can find, it looks like the Seat Heater Module uses some kind of a LAN signal.

The only thing I can really think of off hand is if, for example, the Volt heat has different resistance than the Bolt heater and THAT'S what measured by the Control Module. That's a total guess, but there aren't any temperature sensors in the seat, and for safety at a minimum, the car needs some way to monitor it.

In theory, a resistor could be installed inline to give the correct signal, IF that's actually how the car works.

When I drove the car yesterday, I certain DID miss the seat heater! Leather in the cold is colder than cloth in the cold!

Since the "Hot Glue Test" seemed to go pretty well, I decided to do this for the car. There's more wires in more rows than on my test piece, so it didn't look as nice, but in the end the wires are held in well. I can unplug and replug it and all the terminals go where they are supposed to.

The plug did pull out nice and clean. No gunk where it shouldn't be.

Since the Bolt 2LT has a power driver seat, there is 12V+ available to the seat all the time, so you can adjust the seat before you hop in. Unfortunately, that also means that the heated seat (while not properly controlled by the wrong module) is ALWAYS ON! Great way to burn your butt AND kill the 12V battery when parked.

I cut the main 12V wire on my custom pig-tail and added a pair of male/female spade connectors. Then I wired up a length of 2-conductor cable to a beefy power switch. I simply inserted the switch inline with the 12V power.

With the switch on, the seat heats up. With it off, it doesn't. Nice and simple. Not elegant, but effective. I at least want the heated seat for now, and I can still continue working on figuring out how to get it fully integrated.

For anyone wondering, the seat draws less than 5A of current.

Tune in for future updates as I continue to work on this.