For a long time my 2004 regular cab truck has a quirk that both the driver (and passenger if present) must click their seat belts before starting the truck. If not, the seat belt chime and light flash, even though the seat belt light is off when the alarm is not sounding.

Even if the truck is in park, and the passenger gets out of the truck and back again with the engine running, once in drive it will start the seat belt alarm with everybody properly buckled.

A few months ago I was driving to work and the airbag light started to flash.

I took the truck in for the air bag wiring harness recall, and the airbag light did not flash since then, and for a little while the seatbelt problem went away.

1 month later the seat belt quirk was back again.

This past weekend the 5x5 air bag alert started. I checked previous posts, and confirmed that my air bag light does not ever light on my dash. I don't remember if it ever came on once the recall was "fixed".

My gut feel is that the wiring to the light is fine, and that this is a wiring problem in the harness. I saw a post that made a vague reference to the air bag sensor under the center console and the seat belt circuit and could find no more.

Does any body have a wiring diagram?

If the airbag light is out, does the 5x5 alert supposed to indicate that the bulb is burned out, or that the bulb is out AND there is an airbag fault?

Has any body experienced this quirky seat belt phenomena?

 

Unless you plan on disconnecting every single component in the restraint system and ohming out each circuit, a wiring diagram really isn't going to help you. You need to be able to link up with the restraint control module (RCM) and the instrument cluster, and see the live data to determine what is going on.

The airbag warning chime only indicates that the RCM sees an error on the indicator light circuit, as it is a critical component of the system. A failed indicator bulb or circuit in itself sets a fault code, so yes, you have fault codes in the RCM.

There is no airbag sensor in the console, it is the RCM itself, which controls the deployment of the airbags. DON'T mess with it unless you disconnect the battery and wait 20 minutes, as banging or probing the module or harness can set off the air bags, especially if it has issues like yours appears to have.

I have seen modules cause symptoms like yours due to corrosion of the module circuit boards after water intrusion. I have also seen airbags and pretensioners deploy unexpectedly due to the same issue.

I respect your enthusiasm in trying to repair your own vehicle, but I would highly recommend getting this checked out by a pro, and probably sooner than later.

Jay

 

Today I noticed the that before turn the key to the start position, I will get a brief flash in the odometer display that reads "check gauges" and a single beep of a chime.

I can't say that I'm too excited about working on the truck, but that's mostly because of the cold weather. (Cleveland OH)

I'm engineer who works with a lot sensors and am more comfortable working on electrical problems than mechanical, despite having schooling as a mechanical engineer.

Can I read the RCM with a scan tool? I have one of the OTC Nemisys units, though I think I need a software update.

Maybe it is just a bad light in the dash?

 

Not sure about your scan tool, I only use Ford's IDS system at the dealership. Plug it in and see what happens, cant hurt it doing that.

A burned out airbag light will set fault codes and cause the beeps. It cannot possibly cause your other symptoms, unless something is seriously screwed up inside the RCM, either hardware or software.

 

I have the same problem with my 2006 F-150, my airbag warning chime is going off as well. I have taken it to a ford dealership and they told me that it would cost me $1600 to fix it. They said they had to replace the instrument cluster, passenger air bag light (even though its not burn't out) and front sensor and pigtail. This is what their computer told them the problem was. I also talked to another Ford mechanic and he said that sometimes if they can't figure it out that they just start replacing parts! I am very unsure as to what to do... i don't want to spend the $1600 if that doesn't fix it.

 

At least for the air bar part of the problem, mine turned out to be the sensor mounted on the support right in front of the radiator. You'll need to replace the sensor as well as the connector. My sensor was cracked and the connector corroded. A common problem.

The parts are only available from a dealer. Some claim the sensor can be had for $50, my stealership charged $75. I did the install myself.

 

Thanks!! i will try that next! Is there anything i should know in replacing it, is it just a matter of cutting the wires and splicing a new connector in? I am just worried about setting them off.

 

I just took the sensor off and disconnected the connector... yup!! the pin on the sensor is totally corroded off!! Thanks again!!

 

For me it was the airbag light bulb itself, once the bulb burns out you will get the 5x5 beep every 30 minutes. If you have a problem with your restraint system and you dont fix it, that bulb will burn out from blinking everytime you start up that truck and then it stays lit. So I changed them all while I was at it. And of course fixing what started the airbag light to blink in the first place is a big help. Easy to tell, your airbag light was on,NO chime. Now you have a chime and the light is off. BINGO light bulb.

 

There must be different displays in the trucks. My truck is XLT and the light bulbs only serve as a general back light for the display. The actual "light" for the airbag (and other warning indicators) are surface mount LED's on the main pc board.