C7 Key FOBs both died...how to re-program
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Cruising
Joined: May 2024
Posts: 10
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C7 Key FOBs both died...how to re-program
Has anyone had their Key FOBs just quit working? Both of mine somehow lost contact with the car...I can insert into steering wheel slot and drive, but cannot lock the car. And everytime I start the car, it says theft attempted.
How can I re-link Key FOBs to my car? I put new batteries in both the day this happened, but they will not communicate with the car.
How can I re-link Key FOBs to my car? I put new batteries in both the day this happened, but they will not communicate with the car.
Safety Car
Joined: Dec 2012
Posts: 3,851
Likes: 1,860
From: St. Louis Metro East IL
The fobs ARE PAIRED to the car, otherwise they would not work in the steering column slot. No need to repair (reprogram).
- make sure fob batteries are good - near 3.3 volts and installed properly
- make sure car battery is charged
If neither fob will lock or unlock the doors you may have a remote keyless access problem in the car itself - check fuses. Start with the 2 fuses in the rear fuse block labelled Passive Entry or Keyless Entry.
Most parts stores can verify that the fobs are transmitting or you can buy a fob tester for $20 or so to verify.
I really doubt the fobs are your problem - more likely something in the car.
GL
Ron
- make sure fob batteries are good - near 3.3 volts and installed properly
- make sure car battery is charged
If neither fob will lock or unlock the doors you may have a remote keyless access problem in the car itself - check fuses. Start with the 2 fuses in the rear fuse block labelled Passive Entry or Keyless Entry.
Most parts stores can verify that the fobs are transmitting or you can buy a fob tester for $20 or so to verify.
I really doubt the fobs are your problem - more likely something in the car.
GL
Ron
Last edited by RonC7; May 11, 2026 at 04:07 PM.
Pro
Joined: Jan 2021
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From: Treasure Coast
Safety Car
Joined: Dec 2012
Posts: 3,851
Likes: 1,860
From: St. Louis Metro East IL
I assume that the fobs were working before you changed the batteries.
Yeah, both fobs "died" at the same time. What is common to both fobs? 1) you changed both batteries (potentially weak / dead "new" batteries or BOTH installed incorrectly, 2) the remote keyless entry system.
First check the battery voltage and installation.
Don't go looking for trouble or causing yourself unnecessary work.
(I typically check new battery voltage and then change one fob battery at a time and verify operation)
I wasn't this careful in the old days when I had an ignition key. Now that it's a pain to get into the car without a fob and a pain to start the car I pay more attention...
Ron
Yeah, both fobs "died" at the same time. What is common to both fobs? 1) you changed both batteries (potentially weak / dead "new" batteries or BOTH installed incorrectly, 2) the remote keyless entry system.
First check the battery voltage and installation.
Don't go looking for trouble or causing yourself unnecessary work.
(I typically check new battery voltage and then change one fob battery at a time and verify operation)
I wasn't this careful in the old days when I had an ignition key. Now that it's a pain to get into the car without a fob and a pain to start the car I pay more attention...
Ron
Last edited by RonC7; Today at 01:51 PM.
