Adding Heated Seats

[erg1948]

I bought a '99 LS that is not equipped with heated seats. Now that the weather is turning colder I am beginning to regret that. I am thinking of buying a used LS center console that has the factory switches, then install aftermarket seat heaters. If I can use the factory switches, it would at least look like original equipment. Do you experts think this is do-able? Thanks for any help!

Gene

[1990LS400]

Well... there is a fairly complex 14 pin connector that plugs into the seat heater switch module -- there is not a separate connector for each switch. The repair manuals for my 00 LS400 do not include information about voltages and I do not have the separate electrical manual. I wouldn't know if the switches would be compatible with aftermarket seat heaters.

I'd say that, at the minimum, you would need the connector for the seat heater switches and a few inches of its wiring harness to splice into the wiring harness for your aftermarket seat heaters. Maybe you could get it from a salvage yard or even from Lexus. Lexus sells some partial wiring harnesses for collision repair.

It sounds like a long shot but where there is a will, there is a way. It looks to me that the wiring harness for my seat heaters is built into the wiring harness for other components -- I've removed the console wood from my 00 LS a bunch of time over the years. I doubt if it is available separately but I could be wrong. It's not like European cars where there is can be a separate little wiring harness for an optional item of equipment. I've wired up all sorts of extra features on older Mercedes cars (rear fog lights, headlight wash/wipe, rear seat audio control) and generally on Mercedes its been "plug and play" with all the components including separate wiring harnesses.

Heck, if you want to try this, why not go all the way and obtain a Canadian market console wood that also includes a headlight cleaner switch. That'ill keep you busy! I'll bet the washer nozzles for the bumper are available separately and I suspect that the washer fluid container has a place to plug the headlight washer motor into it like Mercedes cars do. You are fairly close to B.C. which might make it a little easier. I've bought a variety of items, including mudflaps for my 00 LS400, from Metro Lexus in Victoria on Vancouver Island -- the parts guy I worked with is Paul.

If you are worried about cold weather, Canadian dealers sell a fairly inexpensive block heater for your 99 LS.

Good luck with your project.

[erg1948]

Well... there is a fairly complex 14 pin connector that plugs into the seat heater switch module -- there is not a separate connector for each switch. The repair manuals for my 00 LS400 do not include information about voltages and I do not have the separate electrical manual. I wouldn't know if the switches would be compatible with aftermarket seat heaters.

I'd say that, at the minimum, you would need the connector for the seat heater switches and a few inches of its wiring harness to splice into the wiring harness for your aftermarket seat heaters. Maybe you could get it from a salvage yard or even from Lexus. Lexus sells some partial wiring harnesses for collision repair.

It sounds like a long shot but where there is a will, there is a way. It looks to me that the wiring harness for my seat heaters is built into the wiring harness for other components -- I've removed the console wood from my 00 LS a bunch of time over the years. I doubt if it is available separately but I could be wrong. It's not like European cars where there is can be a separate little wiring harness for an optional item of equipment. I've wired up all sorts of extra features on older Mercedes cars (rear fog lights, headlight wash/wipe, rear seat audio control) and generally on Mercedes its been "plug and play" with all the components including separate wiring harnesses.

Heck, if you want to try this, why not go all the way and obtain a Canadian market console wood that also includes a headlight cleaner switch. That'ill keep you busy! I'll bet the washer nozzles for the bumper are available separately and I suspect that the washer fluid container has a place to plug the headlight washer motor into it like Mercedes cars do. You are fairly close to B.C. which might make it a little easier. I've bought a variety of items, including mudflaps for my 00 LS400, from Metro Lexus in Victoria on Vancouver Island -- the parts guy I worked with is Paul.

If you are worried about cold weather, Canadian dealers sell a fairly inexpensive block heater for your 99 LS.

Good luck with your project.

Thanks Jim. It sounds like you have been under the console enough times to know that the plug isn't already there. I was hoping that Lexus would be like some others and have the plug just taped up inside. There is a center console on eBay that I am watching, ~$100 US with shipping. I have a few days to think about it. The console is complete, where all I need is the wood parts and switches. A thought, I could email the seller and see if they could cut the plug off the harness, assuming they still have it.

Thanks again.

Gene

[1990LS400]

Gene,

My 00 LS400 has seat heaters ( the switches can be seen to the left in my avatar) so of course it has all the wiring and connectors. I think I remember that people have verified in the past that LS400s without seat heaters do not have the wiring for them.

It is very easy to remove the wood console panel if you want to verify this. Really, it's a two minute task. Some people use a screw driver but I prefer to use a one inch stiff putty knife with its blade covered with a layer of electrical tape. Start at the sides towards the back of the console wood and gently pry the console wood up -- it is held in place by six friction fittings. Two on either side near the cup holder, two on either side near the gear shift and two on either side near the ash tray.

Be gentle as the console wood is fairly fragile -- way more that the gen 1 LS I had which had much thicker console wood. I use the putty knife to spread the force on the wood and to reduce the chance of cracking it. A screw driver works well as long as you know exactly where the hidden friction fittings are located.

Before the console wood is removed you will need to disconnect the connectors for the VSC button and ash tray light -- it's a little tricky so be patient and perhaps use a flashlight to see how to compress the tab in each connector in order to remove it.

The console wood snaps easily back into place -- much easier than removing it. Don't forget to reconnect the VSC and ashtray connectors first! I forgot once.

Good luck.

[erg1948]

Gene,

My 00 LS400 has seat heaters ( the switches can be seen to the left in my avatar) so of course it has all the wiring and connectors. I think I remember that people have verified in the past that LS400s without seat heaters do not have the wiring for them.

It is very easy to remove the wood console panel if you want to verify this. Really, it's a two minute task. Some people use a screw driver but I prefer to use a one inch stiff putty knife with its blade covered with a layer of electrical tape. Start at the sides towards the back of the console wood and gently pry the console wood up -- it is held in place by six friction fittings. Two on either side near the cup holder, two on either side near the gear shift and two on either side near the ash tray.

Be gentle as the console wood is fairly fragile -- way more that the gen 1 LS I had which had much thicker console wood. I use the putty knife to spread the force on the wood and to reduce the chance of cracking it. A screw driver works well as long as you know exactly where the hidden friction fittings are located.

Before the console wood is removed you will need to disconnect the connectors for the VSC button and ash tray light -- it's a little tricky so be patient and perhaps use a flashlight to see how to compress the tab in each connector in order to remove it.

The console wood snaps easily back into place -- much easier than removing it. Don't forget to reconnect the VSC and ashtray connectors first! I forgot once.

Good luck.

Thanks once again! If I decide to persue this little project I'll post again to let you know how it worked out.

Gene