Toyota key fob stopped working suddenly

[isisdave]

I know there are probably better places to ask, but responses from this group are amazing so I thought I'd try here too.

I have a 2012 Toyota Camry, and a couple of weeks ago the key fob, which only locks/unlocks, opens the trunk, and has a panic button, stopped working overnight. I changed the battery, which didn't help.

The other fob also doesn't work, so I'd guess it's the in-car part of the connection that's the problem.

As there is an actual key part to start the car, this is only a mid-level annoyance, but still ...

Any suggestions? Thanks.

 

[Sunset]

Did you test the battery that you put in ?
I ask as I have a bunch of those types of batteries in the basement , and use them so rarely that I'm sure some have just aged out.

 

[GenXguy]

Was the other fob working recently? When my Toyota fob stopped working at different times because of low battery, it wasn't a sudden thing. It developed over quite a few weeks.

In fact, my key fob for my car needs a new battery now, but I'm using the remote start / alarm fob.

I've had some issues with the Viper remote start in the past that were resolved by disconnecting the car battery for a short while and reconnecting.

 

[Car-Guy]

Make sure your new FOB battery is in properly (negative to negative and positive to positive). Check both FOB's. If that doesn't work, you can try to remove the positive side of your car's battery terminal for a minute then replace it. If none of that works, then it sounds like a mechanic shop visit may be in order.

 

[Tadpole]

I have a Toyota Camery 2011. I replaced the battery a couple of years ago. It had not quit working but the battery replacement seems to have been effective. If you have the quick reference guide for your car, there should be a section that shows how to replace the battery and tells which battery to use. With this information I was able to find a compatible replacement battery at Amazon.

 

[SecondAttempt]

Same thing happened with my partner's 2014 Camry a couple of weeks ago. I replaced batteries and did some other troubleshooting but can't figure it out. Apparently sometimes the programming can be lost due to button pushing sequences that happen accidentally. Yeah...

 

[Texas Proud]

I do not have Toyota but my car required me to push the fob on the start button while starting the car to recognize it... not sure what it did but it worked...

 

[donheff]

I saw a handle on a techie post recently that read: "let me Bing that for you"" instead of the old let me Google that for you. Bing is now ChatGpt4. That prompted me to give it a shot:

Reposition the Fob: Sometimes, the fob’s position matters. Hold it close to the ignition switch or the start button while attempting to start the car. Make sure the fob is within the allowed signal exchange range.

Reset the Fob: If repositioning doesn’t work, try resetting the fob. Here’s how:

Take out the Metal Key: Remove the metal key from the fob.
Door Lock Method: Insert the key into the driver’s door lock and turn it clockwise and counterclockwise ten times.
Glove Compartment Method: If the fob still doesn’t work, find the key switch in the glove compartment and repeat the same process.
Push Button Ignition: For fobs with a push-button start, perform the same steps with the ignition switch.
Check for Damaged Parts:

Inspect the fob for any worn-out buttons or physical damage.
Look for any issues with the key or lock mechanism.
Ensure that the fob’s programming is intact.
Replace or Repair: Once you’ve identified the root cause, replace or repair the damaged part. It could be the fob itself, the lock system, or other electrical components12.

Remember, if these steps don’t resolve the issue, consider seeking professional assistance from a Toyota dealership or an automotive locksmith. They can diagnose and address any deeper problems with the key fob system. ​

Of course, it could be hallucinating. Let us know.

 

[lauradrops]

I had the same issue in my Honda, it was the actuator. Each door has one and if one is bad the fob won't work.

 

[ERD50]

Check the battery in the other fob, and also check specific programming steps for your make/model - there might be some sort of reset/relearn process that you can run through w/o any special equipment (the turn key on, tap brake pedal three times, rub your stomach, say "abra-ca-dabra" type of process).

-ERD50

 

[GenXguy]

I saw a handle on a techie post recently that read: "let me Bing that for you"" instead of the old let me Google that for you. Bing is now ChatGpt4. That prompted me to give it a shot:

Reposition the Fob: Sometimes, the fob’s position matters. Hold it close to the ignition switch or the start button while attempting to start the car. Make sure the fob is within the allowed signal exchange range..​

That doesn't sound relevant to the OPs problem of the fob not working to open doors. I'm very familiar with the model and have replaced the battery in one myself. The key normally will work from quite a ways away. He mentioned both fobs don't work but didn't state if the other one had been in recent use or shut away in a drawer for 10 years. If both keyfobs stopped working at the same time, seems issue is with the car as it is unlikely both would have failed at once. But never got an answer from the OP on that.

When this happened with mine with each key at different times, I just had to replace the battery in the keyfob, and that was it. OP didn't mention having a start button either. He says it uses the actual key to start the car. That's how mine is as well.

 

[donheff]

That doesn't sound relevant to the OPs problem of the fob not working to open doors. I'm very familiar with the model and have replaced the battery in one myself. The key normally will work from quite a ways away. He mentioned both fobs don't work but didn't state if the other one had been in recent use or shut away in a drawer for 10 years. If both keyfobs stopped working at the same time, seems issue is with the car as it is unlikely both would have failed at once. But never got an answer from the OP on that.

When this happened with mine with each key at different times, I just had to replace the battery in the keyfob, and that was it.

I thought I saw the OP mentioned that he replaced the battery to no effect, and was concerned that the Fob might need to be reconnected with the car. So I asked Bing about that.

 

[GenXguy]

I thought I saw the OP mentioned that he replaced the battery to no effect, and was concerned that the Fob might need to be reconnected with the car. So I asked Bing about that.

He did mentioned replacing the battery but didn't follow up if the other fob had been used recently. But he says there is no problem starting the car. I found the starting part still works even when my fob's battery needed to be replaced - it doesn't use the battery for that part. It does need the battery to unlock the doors with the fob.

 

[donheff]

He did mentioned replacing the battery but didn't follow up if the other fob had been used recently. But he says there is no problem starting the car. I found the starting part still works even when my fob's battery needed to be replaced - it doesn't use the battery for that part. It does need the battery to unlock the doors with the fob.

I missed that. I assumed he had a start button or used a physical key to start the car. If the Fob is actually involved in the start, it must still be connected, so some entirely different question is in order. I'm not good enough at prompt engineering to take that one back to Bing.

 

[GenXguy]

I missed that. I assumed he had a start button or used a physical key to start the car. If the Fob is actually involved in the start, it must still be connected, so some entirely different question is in order. I'm not good enough at prompt engineering to take that one back to Bing.

Yeah, that could be right. OP needs to follow up to clarify on that. He's gone silent on the matter.

 

[isisdave]

Holy cow, everyone, it's only been 24 hours since I posted! This isn't exactly crucial, and there are other things in my life.

But thanks for the attention. To recap, the fob only opens doors; it has nothing to do with starting the car, thank goodness. This is a 2012 model, and it's only a Camry, so there is no 2024 magic remote start or anything. You start it with the key, and clearly the fob doesn't need to "work" to have it start.

It/they used to work from about 20 feet away, which I always thought was not very great, as other cars' fobs work from a lot farther away. It's useless for finding your car in the parking lot by pressing the panic button.

The main fob stopped working suddenly. One day it worked, and the next day it didn't. It's not like it was getting gradually weaker. I changed the battery anyway, which didn't cure the problem. And I measured the voltage of the old battery, and it was not very much less than the new one.

The spare fob had not been used in a few months, but it didn't work either. I didn't change its battery, because by now I'm thinking the problem is at the receiver in the car.

The most useful suggestion I've read so far that is consistent with these facts is to disconnect the battery and reboot everything in the car. I will try that today or tomorrow, but I'm delaying because I know it'll make the radio forget all its saved stations.

What I was hoping for is someone who says "yes, I have a Toyota of a similar year, and mine did the same thing! What fixed it was .... "

Thank you all again, and best wishes for a happy holiday season and great new year.

 

[GenXguy]

But thanks for the attention. To recap, the fob only opens doors; it has nothing to do with starting the car, thank goodness. This is a 2012 model, and it's only a Camry, so there is no 2024 magic remote start or anything. You start it with the key, and clearly the fob doesn't need to "work" to have it start.

Mine is an older Camry, but there's an RFID chip that is used in the key to enable the car to start, even though you still have to insert the metal part of the key and turn it to start it. That still works in my keys despite the dead battery - that's by design. So, your model almost certainly still has that security feature, but that's unrelated to unlocking the doors, which uses the battery to transmit a signal to the car.

It/they used to work from about 20 feet away, which I always thought was not very great, as other cars' fobs work from a lot farther away. It's useless for finding your car in the parking lot by pressing the panic button.

Indeed that is terrible range. Mine works from clear across a parking lock/unlock doors, maybe 150 feet or further and still good with the battery nearing its death. That's all original Toyota before I put the Viper alarm/start in that has an even further range.

This reminds me I still need to change the batteries in both my keys!

Good luck and let us know how it goes.

 

[ERD50]

.... And I measured the voltage of the old battery, and it was not very much less than the new one. ....

More of a general comment, but when asking for help remotely (no pun intended!), it really helps to be specific.

Saying "it was not very much less than the new one." isn't enough info for someone trying to help. I don't know what you consider "not very much less", and these lithium batteries have a very flat discharge curve (I'm assuming a CR2032 coin cell, but again, assumptions can lead to misdiagnose). Maybe the 'new' battery was low (it happens, if they were stored in a hot warehouse or something.

Actual values are much more helpful, and will get you better answers faster. Like "the new battery measured 3.2V, and the old one 3.1V", and even at that, the best way to measure a battery is under load, which an actual battery tester will probably do, but a voltmeter won't.

best wishes for a happy holiday season and great new year.

And you too!

-ERD50

 

[Texas Proud]

Does the doors lock and unlock with the button on the door?


If so, then that is not a problem.

 

[isisdave]

Yes, they do.

The actuators are not the problem, but the inability to unlock the doors remotely is (as mentioned before) a moderate vexation.

Regarding the battery voltage: I didn't mention specifics because (a) I didn't write down the old battery's voltage, but it was about 3.1v; and (b) I measured it with a $6 VOM from Harbor Freight.

 

[ERD50]

Yes, they do.

The actuators are not the problem, but the inability to unlock the doors remotely is (as mentioned before) a moderate vexation.
....

OK, that term alone made this whole thread worthwhile for me! I am definitely going to be working "only a moderate vexation" into future conversations!

... Regarding the battery voltage: I didn't mention specifics because (a) I didn't write down the old battery's voltage, but it was about 3.1v; and (b) I measured it with a $6 VOM from Harbor Freight.

And 3.1 V should be OK, but I'd expect higher on a new cell open circuit, I'll look up some things later on how to test with a load. And even those cheap meters have decent accuracy - I only stopped buying them because the switches would wear out and get intermittent, and I hate not being able to rely on my tools, especially when I'm troubleshooting an intermittent problem!

-ERD50

 

[The Cosmic Avenger]

I Googled "2012 Camry fuse box", and it looks like Fuse 34 is for the "Smart key system" (see image), and Fuse 29 is "Multiplex communication system power door lock, trunk opener switch". I would check those fuses, let us know if either of those are blown, now I'm curious!

 

[lauradrops]

Yes, they do.

The actuators are not the problem, but the inability to unlock the doors remotely is (as mentioned before) a moderate vexation.

Regarding the battery voltage: I didn't mention specifics because (a) I didn't write down the old battery's voltage, but it was about 3.1v; and (b) I measured it with a $6 VOM from Harbor Freight.

That is the exact same problem I had and it was the actuators. The key fob could not lock or unlock my car doors remotely, but glad it is not your actuators. Just curious, how did you check?

 

[isisdave]

Now I'm not sure what you mean by "the actuators". The doors all unlock and lock simultaneously via the switch on the driver door. And none work with the fob, nor does the trunk release or panic alarm.

What did you mean by "the actuators"? How could all four fail at the same time? And did you have it repaired? What was the repair and about what did it cost, please?

 

[lauradrops]

Now I'm not sure what you mean by "the actuators". The doors all unlock and lock simultaneously via the switch on the driver door. And none work with the fob, nor does the trunk release or panic alarm.

What did you mean by "the actuators"? How could all four fail at the same time? And did you have it repaired? What was the repair and about what did it cost, please?

My doors were locking and unlocking simultaneously via the switch on the drivers door as well. Nothing would lock or unlock with the fob and my auto start would not function either. Took it to the dealer and they replaced the actuator (there is one in each door). Have had 3 replaced, I will need the 4th one as well, but because it is covered under my warranty the 4th needs to fail before they will replace it. It was explained to me that when one or more actuators go bad, the key fob will not work on any of the doors.

I do not know the price because it was warranty work and cost me nothing.

We drove ourselves crazy troubleshooting the batteries, the trunk latch connections and even the sensor that lets the car know the hood is latched because I had read these can cause these issues. I had never heard of the actuators before.