Failed driver's seat weight sensor - downsides to ignoring? Repair cost estimate?

[OrbiterTI4]

After a few days of "off-nominal performance" (described below), figured out today the seat weight sensor for the driver's seat has failed. There were no obvious cable disconnections below the seat that I could see, so I do believe this is a failure above/beyond just a physical switch disconnect.

Observed symptoms of the sensor being out:
Car puts itself in park if in reverse with seat belt unbuckled
Car doesn't know the driver is inside, so unless driver has brake pedal depressed, car turns off as soon driver's door is closed.
No auto-Bluetooth connections - must manually connect every time.

Anyone else had this happen? Any other symptoms/failures happening or about to happen that I just haven't stumbled into yet? And the thousand dollar question - any one seen an estimate before? I'm half expecting the response on the app to be the entire seat has to be replaced.

 

[father_of_6]

The seat heaters might not work without weight triggering. I think the even bigger problem is that these behaviors could change with a software update.

Maybe you can swap the weight sensor from the passenger seat somehow?

Probably worth just having it fixed. No idea how much. My guess... one MILLION dollars.

 

[OrbiterTI4]

In an interesting update, I found out that the sensor has NOT failed, but rather is intermittently failing; I have now had multiple instances where it failed into the ON position and kept the car on indefinitely after everyone exited the vehicle and I closed the door.

Still no service estimate so I don't have a dollar figure yet.

 

[2101Guy]

I have now had multiple instances where it failed into the ON position and kept the car on indefinitely after everyone exited the vehicle and I closed the door.

Still no service estimate so I don't have a dollar figure yet.

Having this same issue on my 2022 LR. It’s maybe 15% of the time. Going to try a reboot first before opening a ticket.

Can you update this thread once fixed?

 

[OrbiterTI4]

Finally heard back from Tesla, because they don't do anything on a service ticket until 48 hrs prior to the scheduled time. Surprisingly it was a phone call and not an in-app or email response, because the service rep was still not 100% sure on what repair work needed to be performed and didn't want to generate an official PDF estimate unless I wanted to actually move forward with the service.

From the Tesla rep: he was trying to come up with a repair procedure and $ estimate based on previous service rep reports and any service bulletins he could find. He believes my generation of Model S has everything associated with the sensor buried within the seat cushion (@2101Guy he said its location did change at some point to match the Model 3 setup, so I don't have a good answer for your new model); the verbal "either spot-on or a little over the top" estimate was going to be $1300.

 

[David.85D]

Have had this problem in the past on a BMW and a MINI. Both issued a recall / extended warranty to 10 years. For both, it required changing out the seat.

Everyone experiencing this, report it to NHTSB…

 

[drtimhill]

After a few days of "off-nominal performance" (described below), figured out today the seat weight sensor for the driver's seat has failed. There were no obvious cable disconnections below the seat that I could see, so I do believe this is a failure above/beyond just a physical switch disconnect.

Observed symptoms of the sensor being out:
Car puts itself in park if in reverse with seat belt unbuckled
Car doesn't know the driver is inside, so unless driver has brake pedal depressed, car turns off as soon driver's door is closed.
No auto-Bluetooth connections - must manually connect every time.

Anyone else had this happen? Any other symptoms/failures happening or about to happen that I just haven't stumbled into yet? And the thousand dollar question - any one seen an estimate before? I'm half expecting the response on the app to be the entire seat has to be replaced.

Airbag deployment issues without this? In which case its a safety hazard.

 

[Samcas]

I have the same problem from a few days ago. Opening a ticket now.

 

[OrbiterTI4]

I have the same problem from a few days ago. Opening a ticket now.

What year of car / generation of seat?

Updating my experience: still haven't done any repairs. My first desire is to unplug/measure resistance/replug the existing sensor, to see if I can verify a break or maybe fix things just by disconnecting/reconnecting. For the life of me, I cannot get the sensor unplugged while the seat is installed, so I need to apparently unbolt the seat and power down the car to do so.

Not sure if there is computer logic to deal with a faulty/failed sensor, or the sensor is just slow to update, but I've found that if I sit in the car long enough after parking before opening the door, AFTER I get out of the seat, the instrument cluster will show "Car Off" and will indeed turn off when I close the door. Likewise, if I wait long enough to close the door after sitting down, even without holding the brake in the car will stay on when I close the door.

 

[Samcas]

What year of car / generation of seat?

Updating my experience: still haven't done any repairs. My first desire is to unplug/measure resistance/replug the existing sensor, to see if I can verify a break or maybe fix things just by disconnecting/reconnecting. For the life of me, I cannot get the sensor unplugged while the seat is installed, so I need to apparently unbolt the seat and power down the car to do so.

Not sure if there is computer logic to deal with a faulty/failed sensor, or the sensor is just slow to update, but I've found that if I sit in the car long enough after parking before opening the door, AFTER I get out of the seat, the instrument cluster will show "Car Off" and will indeed turn off when I close the door. Likewise, if I wait long enough to close the door after sitting down, even without holding the brake in the car will stay on when I close the door.

It’s a 2021 LR MY. Already scheduled service appointment in two weeks. Will see. Almost for sure it’s the sensor problem.

 

[P3dStealth]

Oddly this just started happening to me and I have a model 3. Same exact symptoms.

 

[cleverscreenam]

My driver's seat sensor broke on my 2014 a few years ago. It's an on/off switch but uses a certain resistance for on and off from a circuit on the sensor, so the car can tell the difference between on/off and plugged in/unplugged. After unbolting the seat I easily unplugged the seat sensor 2 wire plug from the rest of the seat, and removed the sensor/circuit board.
Car works fine, when the screen shuts off after door shut, I just tap the MCU to turn back on. If it doesn't, I just reach back and open the rear door slightly ajar.

The passenger seat uses some kind of fluid? sensor that detects the weight of the occupant in order to adjust the force of the airbag, so they aren't easily interchangable.

Here's a seat sensor on eBay for $40, some say it's for the rear? TESLA MODEL S Seat Mat Pressure Sensor 1005778-00-B 2016 | eBay

Don't mind the duct tape on my seat sensor, I was activating it manually with locking pliers (to force my car to stay on with the door open) and didnt want the short the circuit board.

It's long-annoyed me that you can't buy this sensor anywhere, you'll have to find someone selling salvage/crashed car parts to get a replacement (and they might not want to devalue a seat sale by removing the sensor).

 

[efraimbart]

In an interesting update, I found out that the sensor has NOT failed, but rather is intermittently failing; I have now had multiple instances where it failed into the ON position and kept the car on indefinitely after everyone exited the vehicle and I closed the door.

Still no service estimate so I don't have a dollar figure yet.

I think it's less likely that this is an intermittent issues and more likely that the sequence of opening and closing the doors has the vehicle somewhat confused of if you're coming or going due to the lack of sensor input.

 

[efraimbart]

I've posted some other sympoms I've noticed in this thread

 

[M3mom]

After a few days of "off-nominal performance" (described below), figured out today the seat weight sensor for the driver's seat has failed. There were no obvious cable disconnections below the seat that I could see, so I do believe this is a failure above/beyond just a physical switch disconnect.

Observed symptoms of the sensor being out:
Car puts itself in park if in reverse with seat belt unbuckled
Car doesn't know the driver is inside, so unless driver has brake pedal depressed, car turns off as soon driver's door is closed.
No auto-Bluetooth connections - must manually connect every time.

Anyone else had this happen? Any other symptoms/failures happening or about to happen that I just haven't stumbled into yet? And the thousand dollar question - any one seen an estimate before? I'm half expecting the response on the app to be the entire seat has to be replaced.

I just got an estimate for the sensor because my car keeps throwing itself into park. It is $226.00 in Houston, TX.

 

[CloudCowboy]

I submitted a report to NHTSA today.

“The seat weight sensors are failing in my 2022 Tesla Model 3 Long Range. I have been noticing this issue for several months now. I have owned the car since new (February 15, 2022) with 7 miles on the odometer. When I open the drivers door, the car powers up, screen turns on and HVAC system activates. When I close the drivers door while sitting in the drivers seat with the car in park and seat belt unfastened, the screen switches off and the HVAC system switches off. Only if I move around in the seat or depress the brake pedal does the screen power up and the HVAC system activate. I went to the Tesla service facility and they informed me that they are “seeing seat sensors failing on newer cars” and “not sure how many are failing”. Based on what they observed with my car and my description of the issues they said my seat weight sensor is failing.
Also, if I put the car in reverse with the seatbelt unfastened to move the car back a few feet in my garage, the car will sometimes automatically shift to park and display a caution message that “shifted to park to prevent roll away”. The service center informed me that they are replacing failed sensors with the exact same part. My concern is the manufacturer remedy does not replace failed parts with improved design and that this has the potential to cause other safety issues if occupant detection compromised by faulty sensors.”

 

[CloudCowboy]

For reference the exact part is Resistive Occupancy 1099592-00-D

 

[P3dStealth]

Mine was replaced under warranty. Has not happened since.

 

[cleverscreenam]

I just got an estimate for the sensor because my car keeps throwing itself into park. It is $226.00 in Houston, TX.

even with your seat belt buckled?? (if you're turning around backwards, just buckle the seat belt behind you without it wrapped around you.)

 

[CloudCowboy]

I’m just of the school of thought that thngs should work as it was intended to and at nearly $60k, it absolutely should.