Random Keyfob failure

[ChiQiD]

My 2015 Ford Explorer Limited keyfobs are randomly failing to open doors, start, remote start or the key is not detected. I have replaced batteries in both keyfobs, disconnected/reconnected my car battery and been digging all over the internet for this issue. Sometimes the car will start and sometimes it won't. I don't even get the no key detected message sometimes. Other times, it remote starts, opens the doors, lifts the tailgate and does what it's supposed to do.

 

[gary94080]

sounds like a dealer service issue, unless you have a local garage that has a lot of experience in these issues.

one thing you might want to try is looking for a shop that repairs smart phones, tablets and computers. the one that my sister uses also handles replacement key fobs. they might have some ideas that may help.

 

[J_C]

If it's the type with the rubber membrane buttons, try opening it and scrubbing both the back, conductive side of the rubber, and the circuit board traces they contact, with strong, hot detergent solution. That's if a first attempt with a dry cotton swab doesn't get the goo off. The rubber slowly releases silicone oil which is dielectric. If the circuit board contacts are coated in black carbon or gold, take care not to wear away that coating.

Edit: Forgot to mention, the safest way to do this is to make sure you are earth grounded or working on an ESD safe surface, "IF" there's a risk of static electricity in the area.

 

[gary94080]

I remember doing that with TV remotes and game controllers many years ago. sometimes the back of the membranes looked like there was a layer of Vaseline on the surface.

 

[peterk9]

My 2015 Ford Explorer Limited keyfobs are randomly failing to open doors, start, remote start or the key is not detected. I have replaced batteries in both keyfobs, disconnected/reconnected my car battery and been digging all over the internet for this issue. Sometimes the car will start and sometimes it won't. I don't even get the no key detected message sometimes. Other times, it remote starts, opens the doors, lifts the tailgate and does what it's supposed to do.

Welcome to the Forum.
Hi Gary. When you replaced the fob batteries did you clean off the grease? This is a dielectric grease that is there to help protect against moisture and should not be removed as per the manual. Do you have anything constantly plugged into the power point or USB port? Members have noted that having items plugged in has negatively affected the ability to remotely start the vehicle.

Peter

 

[J_C]

^ If removing the grease caused a problem, there would be corrosion present. I'd HOPE that if there is corrosion present, ChiQiD didn't forget to mention that.

 

[gary94080]

Welcome to the Forum.
Hi Gary. When you replaced the fob batteries did you clean off the grease? This is a dielectric grease that is there to help protect against moisture and should not be removed as per the manual. Do you have anything constantly plugged into the power point or USB port? Members have noted that having items plugged in has negatively affected the ability to remotely start the vehicle.

Peter

not the OP, that would be ChiQiD.

I have a USB drive and frequently a cell phone plugged into the USB ports. so far I haven't noticed any issues with the key fobs other than sometimes I have a problem if the fob is too low it doesn't get recognized.

 

[ChiQiD]

I don't remember any grease on the batteries. I had a litter bag covering the back of the console. I've moved it hoping that it was interfering with the antenna receiver.....but.... i doubt that's it. Funny thing though, On page 191 of my owners manual, I found this: Failure to Start: If you can not start the engine after 3 failed attempts do this: 1. Fully Press the brake pedal. 2. Fully press the accelerator pedal and hold it there. 3. Start the engine. Yesterday, I had no troubles starting (since moving the litter bag).... Will try this from the owners manual... and if that doesn't work - probably replace keyfob batteries - again. Will update when something happens .. but..only making 1 change at a time to see if I can figure this out.

 

[J_C]

If you have a multimeter you can check the battery, should definitely work at 3.0V if not lower.

I'd guess the owner's manual page you saw was just about having a flooded engine possibility after 3 attempts, so holding the gas pedal down shuts off the injectors to clear the unburnt fuel out. That would be a situation where it's cranking, not doing nothing from failure of some circuit or fob or signal reception, etc.

 

[peterk9]

not the OP, that would be ChiQiD.

I have a USB drive and frequently a cell phone plugged into the USB ports. so far I haven't noticed any issues with the key fobs other than sometimes I have a problem if the fob is too low it doesn't get recognized.

Sorry about that Gary. I wonder if ChiQiD is an ABBA fan? That's the first thing that came to mind when I saw the name.

Peter

 

[kootenay]

My 2015 Ford Explorer Limited keyfobs are randomly failing to open doors, start, remote start or the key is not detected. I have replaced batteries in both keyfobs, disconnected/reconnected my car battery and been digging all over the internet for this issue. Sometimes the car will start and sometimes it won't. I don't even get the no key detected message sometimes. Other times, it remote starts, opens the doors, lifts the tailgate and does what it's supposed to do.

I have been having a similar issue, randomly not detecting my keyfob, having to use the fob to unlock the doors as opposed to using the sensor in the door handle. And then today, I stopped for gas, and shut down the motor, and was greeted with a "key not detected, restart motor now" message. Hit the dash button to do that, and everything shut down. Only thing the fob would do after that is lock and unlock the doors. Stuck in park. Found my other fob, hoping my first fob had a dead battery, but the condition remained the same.

 

[peterk9]

Were you able to get it running again?

Peter

 

[kootenay]

Were you able to get it running again?

Peter

No, it had to be towed. It's now sitting at a dealership waiting for Tuesday morning opening.

 

[kootenay]

And the diagnosis for my issues was: shorted (broken?) wire between a couple of the control modules behind the dash. Replaced a wire and a relay. The repair was merely overlaying a wire, rather than replacing the wire harness, in order to avoid removing the dash and running up the labour bill even further.
As it was, 5 hours labour charged.

 

[J_C]

^ Glad you got it sorted. Had any prior work or mods been done in that area to disturb the wiring?

Seems kind of like a long 5 hr to charge for, if they didn't even have to remove the dash! Then again, time to research the issue is something more mechanics/shops are billing for.

 

[kootenay]

^ Glad you got it sorted. Had any prior work or mods been done in that area to disturb the wiring?

Seems kind of like a long 5 hr to charge for, if they didn't even have to remove the dash! Then again, time to research the issue is something more mechanics/shops are billing for.

I've not done anything to the vehicle.
It does have DVD players attached to both front headrests for the rear passengers to watch ski and snowboard videos, but I am unclear if they are factory, dealer or after-market options.
They did have the vehicle for close to 20 hours for diagnosis...
And they found the issue at least before replacing a control module or two.

Interestingly, the fobs would lock and unlock all the doors, but the lock buttons on the drivers side would only lock and unlock a few of the doors - quite a bizarre set of conditions.


That being said, my first four cars each cost less than this repair though....gdi I'm old.