Lost All Power To Driver's Seat (Passenger Seat Works Fine)

[Brent Foster]

I've lost all power to my driver's seat and the seatbelt light on the dash constantly flashes. The powered passenger seat works fine. I found a 30A fuse under the dash, but it controls both seats. I checked it, plus, since the passenger side is working the fuse is still good. I'm at a loss. Any help is greatly appreciated.

[steve2006]

Hi and welcome to the LOC.

You are correct in that the power to both seats comes from a common source, did this fault occur when or shortly after you made seat adjustments?

The seat control unit is mounted under the seat and this normally means removing the seat to gain access but have a feel underneath 1st just in case a wiring loom plug has come out or give the loom a shake whilst operating one of the buttons to see if there is an intermittent connection.

The seat belt warning system amongst others is fed off a different fuse so I would look for that loose plug and socket under the seat 1st

[Brent Foster]

I've lost all power to my driver's seat and the seatbelt light on the dash constantly flashes. The powered passenger seat works fine. I found a 30A fuse under the dash, but it controls both seats. I checked it, plus, since the passenger side is working the fuse is still good. I'm at a loss. Any help is greatly appreciated.

Thank you for responding. Before the power loss, I had adjusted the seat forward only once and had no problems (no seat belt light flashing). The next day during a trip the seat belt light on the dash started flashing and eventually I tried to adjust the seat again with no luck. So, the seat seemed fine after the slight adjustment forward, then the next day simply lost power. I've checked all connections under the seat and they all appear tight. Is there a hidden fuse under there somewhere? I've also pulled the fuses under the dash and checked them with a meter. This has to be something simple, but I can't seem to find the problem. Thanks again for your help.

[sizbob]

Brent, I have the same problem but no flashing seatbelt light. Will you keep me updated on your progress. I can not figure out private mail on this form. Try siszbob@aol.com

[Brent Foster]

I just got the car back today from a local tech who couldn't locate the problem either. He tested the lead power wire and said there's no power coming to the seat, yet the fuses are good and the passenger seat works fine (same power source I'm told). The light on the seat buckle doesn't illuminate and the seat belt light continues to flash (because there's no power to the buckle). I'm afraid toyota or lexus will charge me a fortune to locate and repair the problem. Anyone know where I can get a wiring diagram? I'll continue to post updates. Thank you.

[Brent Foster]

Hi and welcome to the LOC.

You are correct in that the power to both seats comes from a common source, did this fault occur when or shortly after you made seat adjustments?

The seat control unit is mounted under the seat and this normally means removing the seat to gain access but have a feel underneath 1st just in case a wiring loom plug has come out or give the loom a shake whilst operating one of the buttons to see if there is an intermittent connection.

The seat belt warning system amongst others is fed off a different fuse so I would look for that loose plug and socket under the seat 1st

You mentioned the seat belt warning system is fed off a different fuse. Would you happen to know which fuse that is? I can't find it in my manual. Thanks

[Brent Foster]

Problem resolved! Okay, after looking for loose wires and checking fuses for what must have been a total of 3 hours, the problem was solved by Lexus of Knoxville. There was a wiring harness close to the seat track that was unplugged. I have no idea how I didn't see it, but I'm glad the pros at the dealership got it working. Best part, they didn't charge me a dime.

[landar]

The seat belt warning system amongst others is fed off a different fuse so I would look for that loose plug and socket under the seat 1st

You nailed it Steve!. Good call.

[Brent Foster]

The seat belt warning system amongst others is fed off a different fuse so I would look for that loose plug and socket under the seat 1st

You nailed it Steve!. Good call.

Yes, you nailed it, Steve! Thanks for all of your help. I looked under that seat several times and checked every plug I could see from the front and back. I simply couldn't find it.....just glad it's working again.

[Micah.Berry]

Glad that you got it working, and just as much - that the dealership didn't charge you for the find! Very nice of them!

Micah

[southygrinalds@gmail.com]

The seat belt warning system amongst others is fed off a different fuse so I would look for that loose plug and socket under the seat 1st

You nailed it Steve!. Good call.

Yes, you nailed it, Steve! Thanks for all of your help. I looked under that seat several times and checked every plug I could see from the front and back. I simply couldn't find it.....just glad it's working again.

Brent: I've got a similar problem on a 1997 LS 400... family member moved driver's seat forward yesterday and today it doesn't work. Fuses seem fine, dashboard seat belt light is on, seat buckle light is out, passenger seat movement and buckle light are fine. I'm not finding a loose connection under the seat.

Did the Knoxville dealer tell you which wires were loose by chance? Thanks.

[landar]

Brent did say the unplugged connector was close to the seat track. So you might want to take a powerful flashlight and carefully look for a cable of wires along the track and check the connector.

[southygrinalds@gmail.com]

Brent did say the unplugged connector was close to the seat track. So you might want to take a powerful flashlight and carefully look for a cable of wires along the track and check the connector.

Fixed it (thank you, God!). There is a black lever that hinges front and back, covering a part of the wire harness near the center floor, that appears to have flipped open towards the rear when the seat went forward. I flipped it back towards the front and the seat works fine... I assume the lever was the issue.

Thanks for the insights.

[greu0901]

Alright guys so I bought two replacement seats for my 94 ls400. When I installed the passeneger side, everything worked fine for a couple weeks. Then I moved it all the way forward to fit something in the back. When I began moving it back, it lost all power about 3 seconds in. Now the seat is stuck in a position where no one can sit in it, and it also covers the front bolts that i need to reach to take the seat off.

Now onto the drivers side. When I put the drivers side in, nothing worked except the the back rest would move in and out, but the seat itself did not move back and worth, or up and down. The seatbelt light was illumintated around the holster, so it had to have been recieving power.

In the earlier he mentioned resetting the cut-off. I have located the 3 cutoffs, but I am not sure how to reset it? It has a small hole in it, so I was thinking maybe I need to insert a needle in it to reset it because there are no buttons. I tried to take it off, but it felt pretty sturdy, not like a fuse, so I decided I should ask first. Also right on it in very small letters it says "breaker". I just wanted to make sure this was the right part. There are three of them, above the fuse box. However, I can only get full access to only one. I have access to the hole next one, ( a green one, higher than the first breaker) but I will not be able to take it off with out removing the paneling around it.

So anyways, how do I reset the breaker/cutoff? Is this what I should even be looking for in the first place? My gas cap and power doors work fine (thank god). I really dont want to bring this to lexus and have to pay 500 bucks, i only paid 2 grand for the car. ANY help would be appreciated, thank you guys.

[Vicecity400]

Similar issue don’t know who’s active on the form anymore but I’m still trying to keep the LS platform Alive here in 2022

Put the driver seat on the passenger harness works beautifully put the passenger seat on the passenger harness works beautifully the moment I put the driver seat on the driver side harness nothing except the lumbar support

Confirmed passenger seat works on passenger side driver seat works on passenger side but the driver side does not work on the driver side

 

[paulo57509]

Is this table correct?  Did you try connecting the passenger seat to the driver harness?  On the surface, sounds like you have a driver side harness issue.

Q: Does your car have seat memory function?

 

[Jeremy M.]

On 1/9/2022 at 5:11 PM, Vicecity400 said:

Similar issue don’t know who’s active on the form anymore but I’m still trying to keep the LS platform Alive here in 2022

Put the driver seat on the passenger harness works beautifully put the passenger seat on the passenger harness works beautifully the moment I put the driver seat on the driver side harness nothing except the lumbar support

Confirmed passenger seat works on passenger side driver seat works on passenger side but the driver side does not work on the driver side

 

As stated on this thread, check, double check, and triple check to make sure that you aren't overlooking anything concerning the connectors- obviously unplugged connections, but also any pins inside the connectors that look like they might be making a poor connection. Once you're certain of that, I'd start off by using simple jumper wires (with a fused positive lead, so there's less chance of blowing internals) and delivering power and ground to the seat's harness/motors outside of the car. That's really just to check that the part you're putting in (the seat and all it's internals) is good. In the case that when the seat is powered manually, it moves fine, I'd move on either to checking the switches, since a bad switch will kill the seat just as well as a bad motor or harness, or checking the harness. Included here is a relevant section of the factory manual to make checking the switches and harness easier.

I'm sure it goes without saying, but exercise caution every time you use a jumper lead- the last thing you want is to accidentally graze against some lead and have your seat literally blow up in your face because the airbag was triggered.

be-171.pdf