Airbag System light stays on following dash removal
 

2002 F150 4.6L XL with 25k. I purchased this truck this past April.

In May it began leaking coolant at the heater core. Following teardown guide found elsewhere on this site, I replaced the heater core and everything turned out great...except now the airbag system light comes on, and stays on. No blinking, no codes...just a solid light that stays on.

https://cimg7.ibsrv.net/gimg/www.f15...3093328bd8.jpg

There was one pigtail connector under the top dash access panel that had no mate, that I could find, during re-assembly. I wrote it off as a connector for optional equipment which my truck does not have...

https://cimg6.ibsrv.net/gimg/www.f15...abca9cbb19.jpg

I checked the fuse for the passenger airbag and it is good.

I pulled the module for the pax airbag and the lamp is good, but there is no apparent voltage at the connector...

https://cimg5.ibsrv.net/gimg/www.f15...c31f6c15d1.jpg

https://cimg6.ibsrv.net/gimg/www.f15...ae30176b04.jpg

Finally, the indicator light on the pax module has never illuminated, which I understand should illuminate at startup then turn off...same as the airbag system light on the instrument cluster.

I've got a few months before the state annual inspection and would really like to resolve this if anyone has any suggestions/help/ideas!

Thanks!

I came across a table of airbag trouble codes for a '98 F150...not sure they apply to my '02, but the table says that...

"Air bag indicator lamp on at all times - air bag diagnostic monitor disconnected or inoperative."

Does anyone know where the air bag diagnostic monitor is located on a 2002 model, so I can check this out?

Thanks for any help!

Airbag
 

I've done many heater cores on those trucks more likely than not u missed a ground wire or pinched a wire between something I would start by dropping the steering column and pull cluster out to look in behind there the bulk of the wiring is right there

I admire your tenacity for taking on the huge job of removing the dash and changing the heater core. I may have a leaky evaporator and I watched a video of removing a dash and replacing the heater core in a 98. Wow! That's a big job!

I don't know about the Fords but on the Subaru that I used to have, if you disconnected the air bag system (which they told you to do before working on it) you had to take it to a Stealership to be reset.

Ka-Ching!

All systems are accessible through the OBD2 port