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About 2 weeks ago, the airbag light came on on my car. I used Tech Stream to diagnose and I had a b1650 code (Occupant Classification System related) the front right passenger seat doesn't seem to detect anyone seating in it. Tech Stream showed I needed to do zero point calibration which I tried but it couldn't communicate with the Front Right side Sensor. I went on a whim and replaced the occupant sensor ($180+ down the drain lol).
after replacing the occupant sensor, it no longer shows it needs zero point calibration. But it is still giving me the code b1650. I tried to do Zero Point calibration and it failed to do it. Said it couldn't write to memory.
I thought about bypassing it to make the light go off, but not sure on how to go about doing that.
Anyone ideas on what I could do to fix this issue?
The sensor is built into the underside of your front passenger seat. Check underneath the seat and see if anything under there has damaged a wire or knocked one of the connectors off. It’s recommended that you disconnect your battery (neg pole) when messing around with airbag sensors or one may blow up in your face. The part is about $400.
The Toyota/Lexus folks charge about $100 to recalibrate the weight and remove the code if necessary.
Has your car been rear-ended? Many cars that have this code have been rear-ended.
The sensor is built into the underside of your front passenger seat. Check underneath the seat and see if anything under there has damaged a wire or knocked one of the connectors off. It’s recommended that you disconnect your battery (neg pole) when messing around with airbag sensors or one may blow up in your face. The part is about $400.
The Toyota/Lexus folks charge about $100 to recalibrate the weight and remove the code if necessary.
Has your car been rear-ended? Many cars that have this code have been rear-ended.
No I haven't been rear ended as far as I know. It just happened one morning randomly. I've check under the seat and I see no wire damage or disconnected or loose connections. I've checked on the seat sensitivity today and it won't even register any weight on the seat with the original sensor or the replacement. So I'm making a guess that its the seat it self has something shorted out or broken wire in it that I can't see or find.
What I was wondering don't the seats in this car have some pads in them to detect when someone seats on them? Its what I'm expecting to be messed up. (My thought was maybe my bodyweight when I was riding in the passanger seat I broke it some how lol I'm on the heavy side)
You say you bought a sensor for $180? That’s not an OEM sensor price. When it comes to electronic/electrical issues, these cars can be very finicky and not communicate with the ECU as they should. The b error is stored in the ECU and if it can’t communicate with the sensor because of proprietary reasons, you may not be able to clear it.
Try disconnecting the Negative pole of your battery for about 5 - 10 minutes.
BTW, the sensor does actually weigh the passenger, it’s not just to detect a weighty object.
The "Zero Point Calibration" and "Sensitivity Check" for the Occupancy Classification System MUST be performed if:
The passenger seat has been removed from the vehicle.
The vehicle has been in a collision.
The Occupancy Classification ECU has been replaced.
For any reason, the indicated weight on the passenger seat (using the Lexus Diagnostic Tester) is not within 7 lbs (3.2 kg) of the actual weight on the seat.
Attempting to clear codes during diagnosis or after a repair.
("Zero point calibration" must be performed first in order to properly clear codes.)”.
IOW: Your OCS isn’t working as designed.
Last edited by Richardsr; 02-03-20 at 05:10 PM.
Reason: info
01-31-20, 10:04 AM
05 Lexus ES330 airbag light on (code b1650)
