Key-fob intermittently not working

[3141592ab]

So some backstory, I own a 2016 FR-S. A few weeks ago, my battery died and I needed a jump. I didn't have any issues for a week but then my key-fob stopped unlocking the car first thing in the morning. I would go out to my car and I would have to unlock the car manually. The car would then start fine and have no issues all the way to work. Then out of habit I went to lock the car with the key-fob and it worked fine. It would only not work before the first drive of the day.



Doing some light research, my best guess is that my battery is starting to go but I was hoping someone could provide a second opinion before I start replacing parts.

[DarkPira7e]

Isn't replacing the battery the easiest first troubleshooting step? What could be easier?

This definitely sounds like a weak battery just replace and enjoy

[BlOody_BoOger]

Yea the battery is like what 1.50$ maybe 2$

Sent from my IN2017 using Tapatalk

[norcalpb]

I had a ton of grime built up in both my door lock actuators that made the buttons on my key (or even the button inside the car) not want to work. I replaced both and now both door locks open rapidly fast. This is only the case if you see the red lock indicator wiggle when you try to hit lock/unlock.

If not, then most likely battery.

[Tcoat]

Battery
Don't bother trying the other fob because that battery will be 5 years old as well.
The fob is always searching for a signal so 5 years is actually pretty good life.

[BlOody_BoOger]

Yea and next time you notice your key fob not working simply place the key fob against the push-start and it'll start everytime unless the key fob is completely dead

Sent from my IN2017 using Tapatalk

[JD001]

And, the car makes a pinging sound to tell you if the fob battery is way too low.. Well, I think it does as that is what I recall when my fob battery died..

[FR-S2GT86]

Didn't anyone here notice the one key bit of information that was given to us in the OP's first paragraph? - His battery died and he needed a jump. I'm sure he didn't mean that the battery in his key fob died and needed a jump.

Everyone so far has been looking at the key fob battery, suspecting THAT is bad, but a bad battery in a fob would cause his symptoms to occur continuously until he replaced the battery in the fob. However, he had not described that as the case.

Remember the saying that automotive batteries die in the summer and fail in the winter. Right now in Georgia, where he resides, the temperatures overnight are getting colder, and the fact that the problem only seems to exist first thing in the morning, leads me to believe that it is the battery in his car that is failing, not the battery in his remote.

Remember that whenever an automotive battery dies to the point that it needs to be jumped, unless it's a deep-cycle battery, it suffers permanent damage. Electronics in modern day vehicles are very susceptible to even minor voltage fluctuations or losses.

My suggestion is to have the battery and charging system properly load tested, then go from there. Alternatively, he can leave a trickle charger on the car's battery overnight to see if that remedies the symptom. If it does, it's probably time to replace the battery in the car. This is, of course, AFTER the obvious checks one would make when trying to diagnose electrical problems, i.e. clean up any corrosion and tighten any loose terminals or ground cables to see if that fixes the issue.

To OP, let us know what you eventually find.

[3141592ab]

I was referring to the car's battery, not the fob, as FR-S2GT86 pointed out. As an update, I took it to autozone and their reader said it was due to be replaced. It was the original battery in the car so it isn't unreasonable for it to be starting to go. I can't say for sure about it having fixed the problem until a few more days go by but the initial prognosis is positive.

[3141592ab]

As a final update, the key fob stopped working in the morning again. I replaced the fob battery and haven't had an issue for over a week. I guess the battery failing the load test was just a coincidence.

[FR-S2GT86]

It's not uncommon to have two different problems compounding the issue. Glad to hear that you were able to get them both solved.

[Tcoat]

Originally Posted by FR-S2GT86

It's not uncommon to have two different problems compounding the issue. Glad to hear that you were able to get them both solved.

Also not unusual for a place to sell batteries to say "it is going to go at any minute"
And for people to ignore the obvious root cause and try to find something worse that isn't really there. In this case the answer to the problem was given in the very first response, backed up several times and was still the last thing actually tried. There was not one single symptoms reported that would lead to the car battery being the issue and replacing it did not resolve the issue.

[FR-S2GT86]

Originally Posted by Tcoat

Also not unusual for a place to sell batteries to say "it is going to go at any minute"
And for people to ignore the obvious root cause and try to find something worse that isn't really there. In this case the answer to the problem was given in the very first response, backed up several times and was still the last thing actually tried. There was not one single symptoms reported that would lead to the car battery being the issue and replacing it did not resolve the issue.

I respectfully disagree with PART of what you said:

In his very first paragraph, the OP said his battery died and he needed a jump. That, right there is enough reason for me to replace a 5 year-old battery. Once a lead/acid battery is drained to the point that it needs to be jumped in order to start the vehicle, it has already suffered damage. Electronics in modern cars nowadays are very finicky and can fail simply due to low voltage conditions. It's best to have full voltage, okay to have no voltage as it won't hurt anything that way, but it is very bad to have low voltage. Low voltage conditions weren't really a big deal up until about 35 to 40 years ago due to the simplicity of most vehicle's electrical systems, but it is a whole different ball game now.

Most people nowadays would be lucky to get five years out of a stock battery. I got seven years out of a replacement battery in another Toyota I have, but as soon as it started giving me problems with not holding a charge after making sure the terminals and cables were good, I bought a new one without even having it tested. I was VERY lucky to get as much use out of that battery as I did.

And looking up the service history on my FR-S, I found that the OEM battery had died on the lot before the car was even sold to it's first initial owner. Toyota replaced it under warranty. It is still in the car and doesn't give me any problems since I pulled it out to perform a normal battery terminal cleaning and maintenance to remove the corrosion on the terminals the first week I had it.

But I do agree with you that it is in the interest of an auto parts store to want to sell you a new battery, that's what they do. There are dishonest salesmen out there, and very few of those salesmen have the actual skills to use one of those battery testers properly in a step-by-step troubleshooting procedure (big surprise, huh?). And that's also the reason why you should learn as much as you can about the cars that you own and learn how they work and how to troubleshoot and fix at least minor issues such as was presented here in this thread. You'll save money in the long run, and maybe even enjoy the experience. I know I do.

Maybe our OP is loaded rich and doesn't particularly care about spending $100 for the piece of mind that a brand new automotive battery will bring.

[Tcoat]

Originally Posted by FR-S2GT86

I respectfully disagree with PART of what you said:

In his very first paragraph, the OP said his battery died and he needed a jump. That, right there is enough reason for me to replace a 5 year-old battery. Once a lead/acid battery is drained to the point that it needs to be jumped in order to start the vehicle, it has already suffered damage. Electronics in modern cars nowadays are very finicky and can fail simply due to low voltage conditions. It's best to have full voltage, okay to have no voltage as it won't hurt anything that way, but it is very bad to have low voltage. Low voltage conditions weren't really a big deal up until about 35 to 40 years ago due to the simplicity of most vehicle's electrical systems, but it is a whole different ball game now.

Most people nowadays would be lucky to get five years out of a stock battery. I got seven years out of a replacement battery in another Toyota I have, but as soon as it started giving me problems with not holding a charge after making sure the terminals and cables were good, I bought a new one without even having it tested. I was VERY lucky to get as much use out of that battery as I did.

And looking up the service history on my FR-S, I found that the OEM battery had died on the lot before the car was even sold to it's first initial owner. Toyota replaced it under warranty. It is still in the car and doesn't give me any problems since I pulled it out to perform a normal battery terminal cleaning and maintenance to remove the corrosion on the terminals the first week I had it.

But I do agree with you that it is in the interest of an auto parts store to want to sell you a new battery, that's what they do. There are dishonest salesmen out there, and very few of those salesmen have the actual skills to use one of those battery testers properly in a step-by-step troubleshooting procedure (big surprise, huh?). And that's also the reason why you should learn as much as you can about the cars that you own and learn how they work and how to troubleshoot and fix at least minor issues such as was presented here in this thread. You'll save money in the long run, and maybe even enjoy the experience. I know I do.

Maybe our OP is loaded rich and doesn't particularly care about spending $100 for the piece of mind that a brand new automotive battery will bring.

He was then a week free of issues and had no further starting nor electrical problems other than the fob.
At least he eventually went to step one.

We had a guy on here a few years ago that no matter what the issue was his answer was "your alternator is done you need a new one".
Trunk won't open = Alternator
Tires low on pressure = Alternator
Seat won't move = Alternator

Pretty sure he was in the alternator sales business!