Passenger Airbag Off

We have had a 2006 Prius for almost 2 years now. In the past few months the passenger airbag seemed to become intermittent where the light would say "Off" even with a passenger. More recently it stays that way all the time. Also, the seatbelt warning light does not come on with a passenger when this light says "Off." In my early searches, I found some references to problems with the wiring harness, so I fiddled under the seat. On two separate occasions I have unplugged and plugged in one of the connections and the airbag works. The first time, it only worked once. The second time, it worked for about a day. The first time, the car was off when I unplugged it. The second time, I foolishly did it while we were going down the interstate. When I plugged it back in, the red malfunction light came on. We turned the car off next time traffic stopped and it worked as it should when we turned it back on.

Has anyone experienced this and do you have recommendations for what to do? I don't know if it might be the pin connectors, loose wires, or something else completely.

 

Good idea, I will try that since I already have that cleaner. I unplugged it and plugged it back in a couple times this weekend with no luck, so I'm not as confident I have the problem narrowed down now. It also seems like the red airbag light stays on a bit longer now when the car goes into ready mode than it used to. Or maybe I notice because I am worrying about it. It is the last light to go off, maybe by a full second or more.

 

Does the fact that both the airbag sensor and the seatbelt sensor are not detecting a passenger help narrow down the problem? I can't remember if the seatbelt sensor used to detect lightweight passengers that did not activate the airbag. Now the passenger seatbelt light never lights up, not even a test during startup like every other light on the dash.

 

I'm wondering if the problem lies in the seatbelt switch. The seatbelt indicator never comes on and the airbag light always says off. As I understand it, the airbag light would just say "airbag" if it detected no passenger at all. I'm not sure how to test the switch--I assume the two wires would be a continuity check, but I have no continuity ign on or off and seatbelt buckled or not. I checked on the driver side and I have continuity when it is not buckled and no continuity when buckled. That would lead me to think that if the switch does not have continuity, the car would think the passenger belt is buckled and therefore should be checking to turn the airbag on or off. That partially aligns with the indicator light saying "off" but then it should change to "on" with a heavy passenger. But it doesn't do that.

 

Not a lot of help here, so hopefully this helps the next person. I didn't have the electronics or skills to confirm, so I took it to a local Toyota specialist (not the stealership) for diagnosis. They confirmed the OCS was fine, but the seatbelt buckle was faulty. I ordered a used one for $39 off ebay, had it two days later and installed it in a half hour.

So to summarize the symptoms in my 2006, the dash light on the passenger side always said "Airbag Off" and the fasten seatbelt indicator next to that light never illuminated.

Pretty much the same problem this person had.
Passenger Air Bag stays "off" - need help | PriusChat
Passenger airbag light always "off" position | PriusChat