Changed the driver's side seat to a lightweight racing seat recently. Planning on doing the same for the passenger side so I conducted an experiment to see what's the easiest and cheapest way to do so without triggering the dreaded airbag light.
Conditions:
I took the passenger seat out and put the seat wiring back on with the crash sensor, 2.2 ohms resister for the airbag, and passenger seat occupancy sensor as pictured below. My inital thought was that, without the bag, the Restraint Control Module (RCM), will think that no one's sitting in the seat, but otherwise everything's fine.
I turned the car on after connecting the wiring to the seat harness on the floor. I saw both the airbag light and "PASS AIRBAG OFF" lights on, so something definitely wasn't right.
Hooked up Forscan and found four errors, two related to the "Passenger Seatbelt Sensor" and two for "Occupant Classification System (OCS)". Seatbelt sensor was easy enough to resolve as I only needed to connect the seatbelt buckle. OCS fault was different as the second error for it mentions "low fluid level". I did not realized that the sensor was sensitive enough to detect that there's less volume of "bag fluid" pressing down on it even without a passenger. Tried OCS system reset and recalibration to see if I can fool the RCM to think that reduced fluid volume is the new "normal" but the procedure will not proceed with the error code present. So no, you cannot calibrate your way out of the "low fluid level" error.
To get around this, I bent the tubing with my fingers and kept pressure on it while power cycling the car. Airbag and "PASS AIRBAG OFF" lights stayed off and seat belt reminder came on. So there was enough pressure for the sensor for RCM to think that there was plenty of fluid with a passenger in the seat. I tied the tubing and held it in place with a couple of zip ties, which essentially turned the senor into a passenger occupancy emulator. Took care of the seatbelt minder light by plugging in a seatbelt extender.
For the next phase of this experiment, I found that used Ford Ecosport occupancy sensors with bags can be had for less than $50. Sensor connector looked the same in the picture so I bought one to try and should be arriving this Friday. The bag seems smaller, so it may be easier to place in aftermarket seats.
Conditions:
- Avoid tearing apart the Recaro passenger seat for the passenger occupancy sensor and bag in case I want to swap back or sell the seat later
- Avoid buying a new sensor and bag as cheapest I found online was $260
I took the passenger seat out and put the seat wiring back on with the crash sensor, 2.2 ohms resister for the airbag, and passenger seat occupancy sensor as pictured below. My inital thought was that, without the bag, the Restraint Control Module (RCM), will think that no one's sitting in the seat, but otherwise everything's fine.
I turned the car on after connecting the wiring to the seat harness on the floor. I saw both the airbag light and "PASS AIRBAG OFF" lights on, so something definitely wasn't right.
Hooked up Forscan and found four errors, two related to the "Passenger Seatbelt Sensor" and two for "Occupant Classification System (OCS)". Seatbelt sensor was easy enough to resolve as I only needed to connect the seatbelt buckle. OCS fault was different as the second error for it mentions "low fluid level". I did not realized that the sensor was sensitive enough to detect that there's less volume of "bag fluid" pressing down on it even without a passenger. Tried OCS system reset and recalibration to see if I can fool the RCM to think that reduced fluid volume is the new "normal" but the procedure will not proceed with the error code present. So no, you cannot calibrate your way out of the "low fluid level" error.
To get around this, I bent the tubing with my fingers and kept pressure on it while power cycling the car. Airbag and "PASS AIRBAG OFF" lights stayed off and seat belt reminder came on. So there was enough pressure for the sensor for RCM to think that there was plenty of fluid with a passenger in the seat. I tied the tubing and held it in place with a couple of zip ties, which essentially turned the senor into a passenger occupancy emulator. Took care of the seatbelt minder light by plugging in a seatbelt extender.
For the next phase of this experiment, I found that used Ford Ecosport occupancy sensors with bags can be had for less than $50. Sensor connector looked the same in the picture so I bought one to try and should be arriving this Friday. The bag seems smaller, so it may be easier to place in aftermarket seats.