beeping when ac is on

[MikeAT]

Hello, I'm a new member with a 2002 Explorer. It's been a good vehicle for the past 12 years. I am now experiencing a beeping sound from the glove box when ever the ac is turned on (only ac, not heat). Not sure what is causing it or how to fix it. Any help would be greatly appreciated. Thanks.

 

[Number4]

Is it a beeping or more of a chirp sound. Is it steady or more spaced apart in occurance? What size engine.

 

[MikeAT]

It's a 4.0L v6. The sound is a beeping and the airbag light comes on. It it spaced out...kind of a series of rapid beeps. Sounds like morse code.

 

[Number4]

Well, easiest check first would be to take off the belt and spin the idler and tensioner pulleys. See if they spin freely (bad) or barely do a single rotation. Bearing noises can be odd. It's a free check, so I'd start there. Rule it out.
When the ac is on, it causes an additional load.

 

[MikeAT]

Checked the pulleys and they are working properly. What next?

 

[turborich]

Since the air bag light illuminates I would start looking in that direction. See what codes are stored and go from there...

 

[Number4]

Is the air bag light flashing in a sequence when it comes on?

 

[MikeAT]

Yes, the light flashes to the tune of the beep, but only when the AC is on.

 

[MikeAT]

But its not a recognizable sequence, its a random series of short and long beeps.

 

[Duranged84]

Find the fuse for your air bag system and pull it. See if the light flashing and beeping stops. Next step is to pull the battery cable and let it sit for 20-30 minutes for safety. Open your glove box and push the tabs on the sides to release the door to pull forward and flip it down. Look up at the bottom of the air bag and unplug it's connector. It'll be yellow. Go ahead and hook the battery back up and Check for the noise. Air bag light should remain on and or flash a trouble code for that being unhooked so don't worry too much about it. If noise is gone try reinstalling air bag fuse and restart to check for noise. If no noise still then you may have an air bag malfunctioning dangerously and could possibly go off at any time if plugged in. If noise is still present with it unplugged then go ahead and disconnect battery and wait again, hook air bag back up and investigate farther. May also remove the passenger kick panel and Check the 3 grounds that bolt to the body.

If it's not making noise with air bag unplugged I would take it in or if your comfortable and confident messing with it, pull that thing out and find shop that can maybe test it or find another to swap in to test for the noise before disposing of the original one. If new bag assembly cures the noise and light, I would be even more careful with the bad bag and find a proper way to dispose of it. Maybe a body shop or something.

Let us know what you find.