I have an issue with a low 1 second repeating tone that will come on at random, bother me for 10 seconds, then stop. It doesn't make much sense why it happens and there's no corresponding light to indicate anything. The mechanic who fixed it up when I bought my truck didn't know what its purpose was.

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2004 Ranger 2WD 3.4L Automatic

We have nothing to fear, but fear itself!

Welcome to the forum! it could be something as simple as the seat belt connector or harness under the seat is messed up & the light on the dash has burned out. I'd like to know myself what it is though, makes me pretty curious!

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1999 xlt 2.5l 5-speed Supercab 159k
83 diesel 2.2l na
06 F250 6.0l psd
{click for lol}

When you turn the ignition to run look at the dash, make sure all the lights come on. All the lights should illuminate to indicate the bulbs are functioning then shut off. (Brake, srs, abs, check engine, od off, 4x4, seatbelt, door, engine warning lights etc)

Like Robert said you may have an issue like a seatbelt, door ajar etc but the bulb isn't working but the warning chime still is.

Forgot to mention. Dont rule out magical musical dash gremlins. Burn sage in the cab while chanting the mongolian spirit prayer to get rid of those damn things.

The mechanic I took it to when I bought it was totally baffled by the tone since it'll just come on at random when I'm driving around. The idiot lights all come on when I start the engine like they should.

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2004 Ranger 2WD 3.4L Automatic

We have nothing to fear, but fear itself!

It might be that the door ajar light on the dash is out and the dome lights are turned off and the door switch is not working.
I had the seemingly random 'door ajar' ding ding ding a long time ago. The dome lights and door ajar light on dash would come on too. It would come on and off while driving and sometimes stay on all night (ran the battery down once cause i didn't notice it lol)
I probably squirted some penetrating oil on the switch to get rid of it, it's been so long i don't even recall exactly where it is haha!

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1999 xlt 2.5l 5-speed Supercab 159k
83 diesel 2.2l na
06 F250 6.0l psd
{click for lol}