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Hi,
I replaced the batteries in my smart key fobs, and now I cannot get into the car intermittently. The remote won't work all the time, the light on the fob lights brightly every time consistently.

Even if I left the doors unlocked, sometimes I walk up to the car and the doors are locked. Other times the doors are still open and then when I attempt to start the car the ignition will not turn. Then other times the key fobs operate normal as they should.

I've left the key in the ingition for an extended period of time and it still has issues.

I just had to replace the car's battery due to its age. The voltage on it was only 10 volts. There is a new fully charged battery in it now and the problem with the keys still persist. Not sure if the original battery with low voltage triggered the issue.

Anyone else experience this?! Thanks in advance!
 

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I am having the exact same issue with both my key fobs also a flat battery seemed to trigger the issue, only happens after leaving the car alone for 8 hours or more. Did you ever find the fix ?
 

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Mine doing it too. Sometimes I walk up to the car and it won't unlock, I stand there for a sec and it works. Sometimes it doesn't recognize the key is in the car. It seems like it's losing signal or it possibly gets interfered with by other RF signals. I am GOING to figure this out.
 

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If you have Checked your key fob battery then it is likely the alarm siren box . They have an internal lithium battery that are dying at this age . The whole siren box must be replaced with a new part you can’t just change the battery
 

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Sometimes it doesn't recognize the key is in the car. It seems like it's losing signal or it possibly gets interfered with by other RF signals.
RF only Controls the C/L, it is IR that allows the EIS to turn and start the Car.

Start by cleaning EIS red dot and key red dot (lenses) with a cotton bud, do not use solvents !! Just damp bud with a little water if needs be ;)

RF signal is received and processed for C/L via EIS, so of course this could be a sign of a failing EIS or Key, but try cleaning them first ;)

HTH,
 

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Batteries are new. I found a video showing you how to re-sync your key to your car by inserting the key and holding the lock/unlock for ten seconds then push the unlock 5 times while holding lock down. This seemed to work. I will also clean the eyes. Thanks for the replies and I hope my fix helps someone. Here is a link to the video.
 

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Hi,

Yep, that's the RF Synch, although it doesn't work on all Keys / Cars ;)

Thanks for letting us know the outcome ;)
 
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