Heated Seats Problem Ls400

Slobbo · March 26, 2015

Hi guys. Heated seats aren't working. Switches work and the fuse is ok but the seats don't get hot. Is there a relay somewhere. If so where abouts. Havent managed to id it. Am thinking this is likely the problem as none of them are warming.

It's a 95 btw

WarwickT · March 26, 2015

Rob mine didn't work very well when the Battery was flat, but back to normal once it was fully charged. Tarun

ls400lpg · March 27, 2015

Yes either get the proper Battery size or you need a new seat.

Too much to repair

Malc · March 27, 2015

................ I understand this is not uncommon in the Mk3. My driver's seat hasn't worked since before I bought the car.

It is not an economic repair, neither to fix the busted element nor to replace with a new seat.

ACLex from whom I bought the car in 2011, the then Parts Manager at Lexus Poole Dorset, didn't find the effort worth doing for the reasons: !. cost of a replacement seat ( at cost price ) and 2. It would just go again, the fault is so common and recurring.

My bum doesn't particularly need warming, even on a really cold day.

Malc

Slobbo · March 27, 2015

The thing is none of the seats seem to be working which makes me think it might be a relay. Battery doesn't seem the culprit. Starts very very easily.

Slobbo · March 27, 2015

Just read somewhere else that the Battery needs to be up at around 14v so I will check the Battery voltage first.

lordturns · March 27, 2015

Just read somewhere else that the battery needs to be up at around 14v so I will check the battery voltage first.

Rob - this is a very common problem on the mk3 and you will find it a regular topic of discussion on here....the likely culprit is the elements themselves which will have failed. Also check the cable connection under the seats as this can become dislodged due to rear seat passengers. I think somewhere on the American forum, there is a photo guide of a seat strip down - quite complex and time consuming more than anything, not impossible though :-) there are after market heating elements on eBay too so you may be able to find a good auto electrician to wire them in for you and get it all working.

Slobbo · March 27, 2015

Thanks Jeremy. I know it is a common issue and have read many posts and the threads all seem to say the same thing in that the elements fail however my car whilst old only has 26k miles on it and was never used in winter and none of the elements seem to be working which makes me think it is something other than the elements. I have found very little on faults other than the elements hence my question. I was hoping someone would have had the same issue.

I will check the cables but until this week I don't think anyone has ever sat in the back. (not kidding - 20 years old and never had anyone in the back)

Malc · March 27, 2015

hahahahaha .................... i was going to say summat quite rude, but I'm tooooo refined for that ............. hehehehehe

Malc

LexusCT200H · March 27, 2015

26k miles?!????????!!!!!!!!!!

cruisermark · March 27, 2015

yes omar - here is the original thread link

http://www.lexusownersclub.co.uk/forum/topic/97542-lexus-ls400-26000-miles/

Slobbo · March 27, 2015

Yep it's like new. Their is barely even surface rust on the 20 year exhaust

lordturns · March 27, 2015

I remember this one on eBay very well - totally mint and a great write up....you shouldn't have any problems with your seats, surely on a car with that mileage???

Malc · March 27, 2015

...... not too unusual for comparatively ancient electrics to be a bit challenging, often from underuse sadly,

Malc

oldhazey · March 27, 2015

Mine dont work in the front 95 mk3 but the rears work,but can be repaired if you have the patience.

She has 191000 and expect the elements have broken over all those miles,but does not bother me as its all about the surge of that awesome V8 and the surreal ride from under 500 squid banger

mikeyv · March 28, 2015

I must admit, heated seats are something I could live without, particularly if the price to fix is too high for a Lexus parts manager!!

Hopefully you'll be lucky, and find a simple electrical fault, and a nice easy fix.

As a matter of interest, was the fault declared by the seller on his comprehensive listing?

mr2lad · March 28, 2015

Don't always presume it's the element... As I have a problem on my car and had element changed last week and still isn't working right, and believe it's down to heated seat thermostats relay.... All my other seats heat up correctly ie rears and passenger and only bottom half of my seat doesn't work Correctly on driver side( bottom half starts to heat up then stops and blows cold air at me after 5mins) ....

Here's hoping yours is just a relay as 26k isn't even run in yet so can't see it being wear n tear plus big coincidence that both front seats don't work.... All pointing to a relay or wiring problem... But then again is it only one relay running both seats..... I know on mine it's seperate relays...

run132 · March 28, 2015

I'll add to the 'I've got a '95 with heated seats not working' clan! Having said that, I am not sure I have ever tried them for a about ten years or so! I too can live without them but a heated steering wheel is a nice thing though! If I had one in my LS that didn't work then I would have that fixed! Having said that, I have surprised myself that I have not done something about it as I don't like things working or 'just being so' in my cars. Did someone say extreme OCD?!

mr2lad · March 28, 2015

Since owning my latest LS I have only once switched the heated steering wheel on just to see that it works then switched it straight off lol

lordturns · March 28, 2015

Don't always presume it's the element... As I have a problem on my car and had element changed last week and still isn't working right, and believe it's down to heated seat thermostats relay.... All my other seats heat up correctly ie rears and passenger and only bottom half of my seat doesn't work Correctly on driver side( bottom half starts to heat up then stops and blows cold air at me after 5mins) ....

Here's hoping yours is just a relay as 26k isn't even run in yet so can't see it being wear n tear plus big coincidence that both front seats don't work.... All pointing to a relay or wiring problem... But then again is it only one relay running both seats..... I know on mine it's seperate relays...

Graham, you are bang on - there are a number of relays according to the US Lexus club site and one of the posters on there said that rather than guessing and making assumptions about what the problem is, you just need to find someone with a multimeter who know's what they are doing....diagnosis within 30 mins tops.

mr2lad · March 28, 2015

Lol unlike the lexus garage I put my car too last week who straight away presumed it was element and replaced seat leather/element (all one piece on the 600s ) at a cost of £1350 + vat (warranty job tho) and returned car to me with the same problem lol now cars going back to them on Monday for them to diagnose it CORRECTLY hopefully and sort the crinkly loose leather at same time.....

All this hassle on my car could of been avoided if they checked properly....

Wish I could find out where my relays are so I could swap them around to see if I'm correct with my diagnoses

lordturns · March 29, 2015

Lol unlike the lexus garage I put my car too last week who straight away presumed it was element and replaced seat leather/element (all one piece on the 600s ) at a cost of £1350 + vat (warranty job tho) and returned car to me with the same problem lol now cars going back to them on Monday for them to diagnose it CORRECTLY hopefully and sort the crinkly loose leather at same time.....

All this hassle on my car could of been avoided if they checked properly....

Wish I could find out where my relays are so I could swap them around to see if I'm correct with my diagnoses

Pfffffffft - £1350+VAT ! one of your seats is worth my LS400.....

mr2lad · March 29, 2015

Jeremy that's just for the bottom half of seat and just the leather and element , so you can imagine the price for a full seat and it's workings £££££££££'s

I bet if you where to buy every part needed to build your own car from nuts to frame/engine etc you'd probably be double if not triple the new screen price,

Couple of years ago I nearly had to replace the inside door card for a GS450h I had and was quoted £2200 eh?!!???!!??!??! Just for the door card not any electrics.... Parts are pricey

ROYT · March 29, 2015

Rip off prices, for that sort of cost they should never have failed in the first place!

lordturns · March 29, 2015

£2200 for a door card sans electrics is bonkers......mind you I am about to have two new springs, shocks, shock boots, anti squeal brake shim kit plus ABS sensor clean/replacement done all KYB/Lexus parts. Worthit to keep the car as original as can be and working as it should. Being resourceful I have saved many hundreds of pounds over what I would have paid a 'stealer' for the privilege of supply and fit.

Graham - wonder what it would cost to 'self-build' your LS