Dial-Up sound in dash

[Shawn226]

I don’t think this has been discussed from what I can find. When sitting in my truck with it off, sometimes it sounds like there’s a Dial-Up connection going on behind the dash. Anyone know what causes this, the purpose? Etc?

 

[Jeepwalker]

You haven't visited Russia or China lately have you?

 

[Jeepwalker]

In all seriousness ...does it sound electronic or do you think it could be caused by pressurized air/coolant blowing through a small crack (in the heater core)? Does it occur after you start it in the am?

Or does it seem to correspond to something like moving the hvac floor/vent/def/heat controls (blend doors squeaking) ..or the infotainment system?

 

[GTyankee]

does it sound like like someone pushing buttons on a home phone ?

Or is it the HVAC system resetting everything to the default position

 

[seabrook]

it’s ET!! he’s in your damn dash man!!!

seriously though no i have not heard this in my truck

 

[GTyankee]

when i am in my truck, the radio is on & it shuts off when i open the door to leave.

 

[Shawn226]

In all seriousness ...does it sound electronic or do you think it could be caused by pressurized air/coolant blowing through a small crack (in the heater core)? Does it occur after you start it in the am?

Or does it seem to correspond to something like moving the hvac floor/vent/def/heat controls (blend doors squeaking) ..or the infotainment system?

Yes it sounds electronic. It’s super faint, but it has that chattering that you’d expect when like you called someone that was connected to the internet back in the 90’s/2000’s.

when i am in my truck, the radio is on & it shuts off when i open the door to leave.

That’s probably a better sequence of events. I get somewhere, shut the truck off, and sit in it for a while (I’m a lease operator for a gas company) and after a few minutes it’ll start and is intermittent

 

[Jeepwalker]

Does your vehicle have the dual zone automatic HVAC system?

Blend doors doors do a 'sweep' by geared electric motors after the vehicle is shut off. Or could be the outside air damper. After the sweep it lets the computer know the position of the doors for the future. Sometimes the motors sound funny or the doors squeak. Not sure if that's the source of the sound you're hearing. Sometimes when I'm standing by our Jeep, the blend doors will start to calibrate seemingly out of the blue.

The reason I asked if the HVAC system was dual zone, is because there are more doors to recalibrate.

 

[Shawn226]

Does your vehicle have the dual zone automatic HVAC system?

Blend doors doors do a 'sweep' by geared electric motors after the vehicle is shut off. Or could be the outside air damper. After the sweep it lets the computer know the position of the doors for the future. Sometimes the motors sound funny or the doors squeak. Not sure if that's the source of the sound you're hearing. Sometimes when I'm standing by our Jeep, the blend doors will start to calibrate seemingly out of the blue.

The reason I asked if the HVAC system was dual zone, is because there are more doors to recalibrate.

I think I’ve also heard this before, kinda sounds like plastic being tightened or whatever. I’ll see if I can take a video today when it makes this noise and post it

 

[Shawn226]

Well I guess I can’t post a video…

 

[Dr. Righteous]

I don’t think this has been discussed from what I can find. When sitting in my truck with it off, sometimes it sounds like there’s a Dial-Up connection going on behind the dash. Anyone know what causes this, the purpose? Etc?

Yes, that is the blend door motors in the air handler resetting. Totally normal. Mine does the same thing.