Gen 3 Malfunctioning passenger seat airbag mechanism

Greetings. I haven’t posted here in years but have encountered an issue I need to sort out on a Gen 3 Prius Five passenger airbag system. For background, my disabled wife is 5’ tall but medical treatments have left her at 265 pounds. She uses a Toyota seatbelt extender. I am 5’ 9” and 190 lbs.

1. When I test the system by sitting in the front passenger seat, the “front airbag on” light will illuminate whether I use the extender or just insert the seatbelt into the buckle.

2: But if my heavier wife uses the extender, the light says “passenger airbag off.” I doubt she could get the regular seatbelt around herself.

So, I know the extender will trigger the “on” mechanism … for me, but not for her. And I know the “off/on” light works for me with the regular belt inserted.

Why is the airbag not showing as being “on” when she uses the extender?

Any clues Prius pals?

Eliot
NoVa

 

I don't think there's anything unusual about how she sits in the seat. It does occur to me that perhaps because her stomach is unusually close to the dash that -- if she could stand it and be able to maneuver in and out of the car -- I could try shifting the seat backwards a notch or two to see what happens.

I talked about this with the indy shop that does basic maintenance for me and I'm going to make note of the software/scan tool to see if maybe they can spot something out of the ordinary. Thanks for mentioning that diagnostic. I'd like to avoid the dealer if I can as they'll try to sell me anything and everything associated with the occupant restraint system!

Eliot

 

I don't think there's anything unusual about how she sits in the seat. It does occur to me that perhaps because her stomach is unusually close to the dash that -- if she could stand it and be able to maneuver in and out of the car -- I could try shifting the seat backwards a notch or two to see what happens.

I talked about this with the indy shop that does basic maintenance for me and I'm going to make note of the software/scan tool to see if maybe they can spot something out of the ordinary. Thanks for mentioning that diagnostic. I'd like to avoid the dealer if I can as they'll try to sell me anything and everything associated with the occupant restraint system! It may be interesting trying to see what the software says without taking my wife up to the station to sit in the seat while the tech plugs in to the OBD. She abhors leaving the house, has trouble breathing outside and doesn't like people seeing the shape she's in.

But, we can at least see if the diagnostic tool offers any guidance. Again, thanks.

Eliot

 

Just a quick update to semi-close the loop. Before leaving a medical appointment with my wife last week I pushed the passenger seat all the way back (it had only one position remaining before hitting full stop). The “passenger airbag ON” light it up when she clicked the belt and stayed on for the 12-15 minute run back home.

I won’t declare this solved until we make a return visit to this doctor in two days. If the system operates properly, I’m inclined to figure it can sense how close her, ahem, extended abdomen is to the dash and takes that into account when making the “on/off” decision.

And, yes, I think a scan tool that can handle the basics for Prius and older Jags is in my future, assuming there is such a creature!

I’ll report back after Thursday, but I thank everyone who has chimed in so far.

 

All now seems well. I made the second medical visit with the seat shoved all the way back. The "seatbelt ON" light illuminated as it should. The car passed our state inspection a few days ago and I was assured at about 88K I still had plenty of rear brakes left. Yippee!