Adventures With Key Fobs

[stevj]

Here's a short story for those who may experience a similar situation.

Firstly, in an effort to thwart relay theft, I disabled all vehicle connectivity just after I bought the Maverick. Touching the door handle to unlock the doors is disabled. Vehicle calling Ford to tell them what I've been up to and where, etc., is disabled. Remote start works without the Ford app. Two years and counting and the Maverick has never failed me.

-Until today-

I parked the Maverick at a store, turned it off and, as usual, locked the doors with the inside door button as I climbed out, then went off to buy stuff.
When I came back to the Maverick and pressed the unlock button on the fob - nothing.
Tried a several times. Nothing every time. Went back into the store and bought a new fob battery and replaced it. Still nothing. Vehicle battery? Last resort; there's other things to try first.
While I waited for my wife to deliver the spare fob from home, I tried the fob key; not to gain entry, for fear that it might set off an alarm that I had no way to turn off, but to see if by chance the mechanical door lock was between extremes and was acting as an interlock. After working the key in both directions a few times, I tried the fob again. No joy.
My wife arrived with the spare fob. Worked! All functions normal. I owe her dinner.
Now, just for grins, I tried the "dead" fob and it was now working as well, also now functioning as normal. WTFO?

My guess is that somehow the Maverick "forgot" the fob I use every day and when the spare fob was used, it caused whatever module is listening for fob signals to wake up and remember.
Perhaps I need to start using the fob to lock the doors instead of the inside door switch?

There's no LED on this fob, so couldn't tell if the fob was actually transmitting. There does seem to be provision for one just by the unlock button, but checked both fobs - light not working on either.

When I got home I measured the output of the fob batteries:
Old battery - 3.02V
New battery - 3.19V
I don't think 0.2V is significant enough to make the Maverick stop talking.
It's a 3V battery, so technically....

Anyway, situation resolved for now.
Thanks for listening, and if any of you have some insight into possibilities, please share.

Steve

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[Gray Goose]

I've never heard of the physical key setting off the alarm. I would have just used the key.

 

[Glen Baker LLC]

I've never heard of the physical key setting off the alarm. I would have just used the key.

Locking my 2023 XLT one of these 3 ways will arm the alarm after 20 seconds.
Key FOB
keypad.
Pushing the lock BUTTON when exiting the truck.
Unlocking the truck with a physical key and opening the door, will set off the alarm
Here's a 24 sec. video of the physical key being used to unlock the Maverick and the warning beep of the alarm was going to go off. I had to shut it off before the horn started to beep.

 

[Carlitos_92]

Perhaps I need to start using the fob to lock the doors instead of the inside door switch?

I'm gonna go with a very hesitant "duh..." here, only because I suspect a rolling code timed out or something along those lines.

If you're gonna stay devoted to your attempts at being "off-grid," maybe use your fob in a safe, remote place every so often. Clearly two years is too long of a gap, but since I am only guessing - maybe quarterly?

 

[HeyBales]

I've never heard of the physical key setting off the alarm. I would have just used the key.

If you fob locked - you armed the passive alarm system.
For non-push button start, If you key open the door - you have 30 sec (or 20?) to prove you have a transponder key - by turning it in ignition to On.

In this case - that indeed should have worked, even though push button start. Just get fob inside cab.
Actually - with no Fob lock, it wasn't armed in this case.

But that is how physical key can set off alarm.

 

[stevj]

I've never heard of the physical key setting off the alarm. I would have just used the key.

Not so much using the key, but then opening the door would set off the alarm.

Steve

 

[stevj]

I'm gonna go with a very hesitant "duh..." here, only because I suspect a rolling code timed out or something along those lines.

Inclined to agree. Thanks.

Steve

 

[First Sergeant]

Locking my 2023 XLT one of these 3 ways will arm the alarm after 20 seconds.
Key FOB
keypad.
Pushing the lock BUTTON when exiting the truck.
Unlocking the truck with a physical key and opening the door, will set off the alarm
Here's a 24 sec. video of the physical key being used to unlock the Maverick and the warning beep of the alarm was going to go off. I had to shut it off before the horn started to beep.

Thanks Glen. I rarely open truck with key, but had forgot about the alarm going off and the very short time you have to get in and get key in ignition! I need to remember that!

 

[stevj]

Locking my 2023 XLT one of these 3 ways will arm the alarm after 20 seconds.
Key FOB
keypad.
Pushing the lock BUTTON when exiting the truck.
Unlocking the truck with a physical key and opening the door, will set off the alarm
Here's a 24 sec. video of the physical key being used to unlock the Maverick and the warning beep of the alarm was going to go off. I had to shut it off before the horn started to beep.

Thanks, Glen.
After watching, went and verified with mine and it works exactly the same. My original reluctance to open the door was based on my fob not working and didn't know if I could shut off the alarm.

Steve

 

[HeyBales]

Thanks, Glen.
After watching, went and verified with mine and it works exactly the same. My original reluctance to open the door was based on my fob not working and didn't know if I could shut off the alarm.

Steve

Since your FOB wasn't being read outside the truck, it might not have worked inside the truck.
If the problem was with the fob sending it's info, or the info being accepted.

If the problem was a hiccup on outside receiver - other fob should not have worked.

I think you had correct call - not sure if your locking method sets the alarm - according to manual no.
But still, to get in and fob still not be recognized for alarm to be turned off - ugh.

I guess you could have sat there with clipboard and note how many people ignored a car alarm going off with a person sitting in it. Got a lab coat in the back seat?

 

[Maverick2022XL]

Here's a short story for those who may experience a similar situation.

Firstly, in an effort to thwart relay theft, I disabled all vehicle connectivity just after I bought the Maverick. Touching the door handle to unlock the doors is disabled. Vehicle calling Ford to tell them what I've been up to and where, etc., is disabled. Remote start works without the Ford app. Two years and counting and the Maverick has never failed me.

-Until today-

I parked the Maverick at a store, turned it off and, as usual, locked the doors with the inside door button as I climbed out, then went off to buy stuff.
When I came back to the Maverick and pressed the unlock button on the fob - nothing.
Tried a several times. Nothing every time. Went back into the store and bought a new fob battery and replaced it. Still nothing. Vehicle battery? Last resort; there's other things to try first.
While I waited for my wife to deliver the spare fob from home, I tried the fob key; not to gain entry, for fear that it might set off an alarm that I had no way to turn off, but to see if by chance the mechanical door lock was between extremes and was acting as an interlock. After working the key in both directions a few times, I tried the fob again. No joy.
My wife arrived with the spare fob. Worked! All functions normal. I owe her dinner.
Now, just for grins, I tried the "dead" fob and it was now working as well, also now functioning as normal. WTFO?

My guess is that somehow the Maverick "forgot" the fob I use every day and when the spare fob was used, it caused whatever module is listening for fob signals to wake up and remember.
Perhaps I need to start using the fob to lock the doors instead of the inside door switch?

There's no LED on this fob, so couldn't tell if the fob was actually transmitting. There does seem to be provision for one just by the unlock button, but checked both fobs - light not working on either.

When I got home I measured the output of the fob batteries:
Old battery - 3.02V
New battery - 3.19V
I don't think 0.2V is significant enough to make the Maverick stop talking.
It's a 3V battery, so technically....

Anyway, situation resolved for now.
Thanks for listening, and if any of you have some insight into possibilities, please share.

Steve

2 possbilities

1st the benign option. You somehow pressed the keys on the fob too many times out of range and desynched the sequence counter for the rolling codes or a battery died which would cause the same problem. Key far as I know shouldn't just magically work again without reprogramming.

2nd the malicious option. Someone was running a jammer and stole one of your rolling codes. The attack is simple in that you jam the key it sends the code but the truck doesn't receive it but the person jamming also intercepts that code. It is a one time use code and since it never made it to the receiver it can still be used to to unlock your truck later on. To play it safe you might want to reprogram your keys.

 

[Maverick2022XL]

As far as key fob relay theft the only way to truly thwart that is to store your key fobs in a faraday bag.

 

[HeyBales]

2 possbilities

1st the benign option. You somehow pressed the keys on the fob too many times out of range and desynched the sequence counter for the rolling codes or a battery died which would cause the same problem. Key far as I know shouldn't just magically work again without reprogramming.

2nd the malicious option. Someone was running a jammer and stole one of your rolling codes. The attack is simple in that you jam the key it sends the code but the truck doesn't receive it but the person jamming also intercepts that code. It is a one time use code and since it never made it to the receiver it can still be used to to unlock your truck later on. To play it safe you might want to reprogram your keys.

How would you reprogram your keys - you mean create a new transponder code on them?
And then program the truck to accept them?

Hmmm - only 4 slots available to program in truck for fobs/key transponders.
The minute you change a transponder of your original 2 keys, if that's all you got - you don't have 2 admin keys to add a 3rd key now, or add one of those back.

If you even could change the transponder code in a fob.

If you have a 3rd admin key - then you could only change the transponder in 1 of the current admin keys, and be able to program the truck to accept that newly changed fob. Since only 4 slots.

There would be no way to reprogram your keys - unless you went to dealer - so they could wipe existing slots, program new fobs to the truck.
And if you look up the programming for these keys in a video - nothing is changed on the key anyway - so I'm wondering what this reprogramming of the keys is anyway.

 

[Cancunbadlands]

It happened once to my 2023 BS Badlands, I couldn't open it, I used the key to manually opened it, it start right away. When I got home I got a new fob battery key, problem solved

 

[Maverick2022XL]

How would you reprogram your keys - you mean create a new transponder code on them?
And then program the truck to accept them?

Hmmm - only 4 slots available to program in truck for fobs/key transponders.
The minute you change a transponder of your original 2 keys, if that's all you got - you don't have 2 admin keys to add a 3rd key now, or add one of those back.

If you even could change the transponder code in a fob.

If you have a 3rd admin key - then you could only change the transponder in 1 of the current admin keys, and be able to program the truck to accept that newly changed fob. Since only 4 slots.

There would be no way to reprogram your keys - unless you went to dealer - so they could wipe existing slots, program new fobs to the truck.
And if you look up the programming for these keys in a video - nothing is changed on the key anyway - so I'm wondering what this reprogramming of the keys is anyway.

The codes reset on a reprogram since the vehicle and key need to start a new sequence of codes. I haven't done it myself but you should be able to reprogram them yourself using the ignition method.
Far as I know it is not an actual reprogram but resetting of the immobilizer system that this does.

Plenty of videos on youtube or websites explaining it.
https://www.safetywish.com/how-to-reprogram-a-ford-keyless-fob/

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