B1490 points at the passenger seat rather than at the airbag control module. Hyundai's service manual names it PASSENGER OCCUPANT CLASSIFICATION (OC) SENSOR (BLADDER) DEFECT, and the part it refers to is the sealed bladder built into the front passenger seat cushion. The airbag warning light comes on and the passenger airbag can be suppressed while the code is stored.
Hyundai's passive occupant detection system, shortened to PODS, reads how the seat cushion is loaded rather than weighing the seat frame. A fluid filled bladder sits inside the cushion, a pressure sensor reads it, and the OC module turns that reading into a classification: empty, a child, or an adult large enough for a full deployment. The module reports that classification to the SRSCM, which arms or suppresses the passenger airbag and drives the passenger airbag ON and OFF indicator.
The code is recorded when a defect or a communication error is detected in the OC module circuit. Hyundai's chart runs eight steps: inspect terminals and connectors, check for an open between the OC module and the SRSCM, check for a short to ground, check for a short between terminals, check for a short to the battery line, substitute the OC module, run the PODS reset with the scan tool, then clear and verify the repair.
Hardware, and the hardware is in the seat. B1490 carries no record of a deployment and it is not a fault inside the airbag control module. Hyundai's own inspection order still puts the wiring and the connectors ahead of the sensor, which is worth following, because an under seat connector costs nothing to check and a seat cushion assembly is one of the more expensive parts on the car.
No. An airbag module reset restores crash data stored in the SRSCM, and B1490 lives on the seat side of the system. Repair the sensor or its wiring, then run the PODS reset with a scan tool at the vehicle. Hyundai's procedure has to be done with the front passenger seat empty, and it is required after service or replacement of any part of the passenger seat, including a PODS equipped seat cushion. Skipping it sets B1496, the not calibrated code.
If the vehicle was in a collision and the SRSCM also locked, that part is ours. Send the module in for an airbag module reset. For the seat hardware, we supply genuine OEM occupant classification sensors.
B1490 with this wording comes from Hyundai service data for vehicles equipped with PODS, and the same code chart appears in Hyundai manuals going back to the mid 2000s on models such as Azera, Sonata, Santa Fe, and Tucson. Kia and Genesis vehicles share this family of SRSCM code numbers, though the seat hardware varies by model and year. Other manufacturers assign B1490 to their own systems, so confirm the module before ordering a seat part.
Look under the seat before ordering anything. Move the seat all the way forward, then all the way back, and check the harness for anything crushed against the seat track or pulled tight at the end of travel. Unplug the OC module connector and inspect the terminals for corrosion and spread pins. A wet passenger side carpet is a common history behind this code.
If the wiring checks out, the remaining question is whether the bladder or the module failed, and Hyundai's chart separates those with resistance and voltage checks at the connector. Read the whole code list while you are in there: B1489 covers the PODS control unit, B1495 the belt tension sensor, and B1496 a system that has not been calibrated. If the part is not listed on the site, send us a part request.
Related codes: B1489, B1495, B1496
Keep reading:
Code scope: Hyundai. The same number can mean something different on another manufacturer, so match the code to your make before you act on it.
A reset clears stored crash data. A replacement part fixes a hardware fault. We have read these codes since the nineties and will tell you which one you are looking at.
Genuine OEM, tested, and shipped ground from Jacksonville, Arkansas.
Hyundai parts and codes · Do not see it listed? Request a part or call 501-988-0611.