I have searched and I can't find what this is. 2011 F250 6.7. Its not running related. The sound happens anytime I hit the key less unlock button, open a door and intermittently while truck has been shut down. It sounds like a GSM cell phone near a clock radio but at a one second pulse. Truck has been off for about 18 hours. For some reason I feel like it's reporting back to big brother.

 

I remember something similar being brought up a while ago, check out these threads:

https://www.ford-trucks.com/forums/1...eep-sound.html

https://www.ford-trucks.com/forums/1...ts-in-cab.html

 

Here's a quicker link to my recording of the "sound". Never did get a full explanation of it but it's the general consensus to be a transmission solenoid actuating.

Mystery Sound 2011 Ford Super Duty - YouTube

And yes, it can go off any old time. I can walk into the garage the next day without using a key or anything and might hear it. It must be cycling on some schedule in perpetuity.

 

Yeah mine does it too.

I have no idea why it needs to run randomly, and after shut off for so long.

ANnoying. I hope it doesnt short out or overheat someday....

 

My bet is that it is something linked to the DEF system. Either a pump coming on to make sure that any fluid pulled up the narrow transfer tube via capillary action is taken back into the DEF tank or a function to keep the DEF from freezing. I don't know if they can electrically afford to run the DEF tank heater on a regular basis for a truck that sits, but something needs to prevent the fluid from freezing when a truck sits in very cold conditions.

 

It's not the diesels only, the gas truck have the same buzzing sound.

I think EpicCowlick is correct about being the transmission since both have the same one.

 

There is no thinking, it is the solenoids in the transmission. and they may buzz till whenever. Ford had my truck over 120 days and it could not be resolved.several engineers just scratched there heads. The transmission designing engineer stated the only time you should hear a buzz. is when you just start to put key into ignition,and then only if you had stethescope right on the trans pan. There has not been enough folks raising a concern about it, so i doubt that one will be resolved.

 

You're right on all accounts. I am keeping my radar up on this one though. When I hear that engineers are not sure why it's getting a cycle signal and then combine that with the rare reports of some bad solenoids, well, I would prefer to have a failure within the warranty period. Still have a ways to go until I have to make the call and either just let it go or press for a resolution.

It is good to have the video though as proof of the "issue" (if you can call it that). This came up right after the 10B17 flash and at the time I figured it was an intended action. It would be reasonable that the engineers would prefer the parts are cycled on a regular basis to keep them lubricated. Kind of like starting an idled vehicle once a month. Maybe they just thought that some seal needed fresh trans fluid on it all the time? Who knows. Your comment about them not knowing why it cycles doesn't add up. In the best case, maybe the guys who looked at your truck were simply unaware of the new firmware command. In the worst case, we have a part that has a mind of its own. Even that doesn't make sense either since it didn't do it until after the flash. Where's the shrugging shoulders/I dunno emoticon?

 

It sure seems like that may be what's happening. It is so much easier to fix a hardware issue with new firmware.

 

Well at least i know i gave my 200% on trying to get that issue resolved.So others wouldnt have to fight the crazy fight. But i guess the only way to get some things resolved is Mass numbers of people complaining.