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.



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...



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...





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!

 

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