Key Fobs Not Detected

[G-59468]

All of a sudden after 5 years, I have an issue in my 2018 GT where it wont recognize either key fob. One day the button on the door handle and both fobs stopped working for a few hours, then the next day the same thing happened. For the passed week and a half the fobs/unlock button have not worked at all. I can still get in and start it manually, but my dashboard constantly says keys not detected when both are present. I know it isn't the fob batteries since the red light blinks on both and started at the exact same time, but was wondering if anyone has had a similar issue??

 

[Hawk853]

All of a sudden after 5 years, I have an issue in my 2018 GT where it wont recognize either key fob. One day the button on the door handle and both fobs stopped working for a few hours, then the next day the same thing happened. For the passed week and a half the fobs/unlock button have not worked at all. I can still get in and start it manually, but my dashboard constantly says keys not detected when both are present. I know it isn't the fob batteries since the red light blinks on both and started at the exact same time, but was wondering if anyone has had a similar issue??

I’d still try installing new batteries. It a cheap first step to eliminate it as a possibility. That LED will probably light up with very little charge.

Otherwise, hooking it up to a Kia diagnostic tool might tell you something.

 

[NS_Stinger]

100% dying keyfob batteries. The battery doesn't just stop working suddenly on the fobs when it gets weak it starts doing shit exactly like you're experiencing. I know because I just had to replace the battery on both of mine for exactly this reason and I'm almost exactly 5 years of ownership too.

 

[Snicklefritz]

I replaced both fob batteries at around three and a half years because the range started to get shorter that I could turn and lock the car since I forget a lot as Ima heading across a parking lot, had to step back toward the car until it would respond and lock and flash the lights and turn the mirrors in. that was my first warning that the batteries were getting soft. they're cheap and easy to put in so why not.

 

[ThunderBoy724]

.

 

[D.J.]

I can still get in and start it manually, but my dashboard constantly says keys not detected when both are present.

you car said "Keys not detected" and still started?
This doesn't sound right.

 

[Grump]

For anyone that might find this in the future or with google.....

Both my fobs stopped being detected in the car and I have to "push to start" with the key itself.
The car detects me when I walk up, mirrors unfold, etc.
The smart trunk beeps but never opens.
The buttons on the door handles dont work.
All functions of the fob (lock/unlock/trunk) work fine at regular distances.
Batteries in fobs were changed, pulled the main battery, and main battery checks out. Nothing helped.

Took it to the dealership and they diagnosed integrated body control unit (IBU) part 95400J5BK0.
Their diagnosis was the antennas failed/detected every other time regardless of fob and suspected failure in SMK (part of IBU).
They also tried a reprogram which did not work.

New one hasn't been swapped in yet but when it does I'll update this post.

 

[D.J.]

For anyone that might find this in the future or with google.....

Both my fobs stopped being detected in the car and I have to "push to start" with the key itself.
The car detects me when I walk up, mirrors unfold, etc.
The smart trunk beeps but never opens.
The buttons on the door handles dont work.
All functions of the fob (lock/unlock/trunk) work fine at regular distances.
Batteries in fobs were changed, pulled the main battery, and main battery checks out. Nothing helped.

Took it to the dealership and they diagnosed integrated body control unit (IBU) part 95400J5BK0.
Their diagnosis was the antennas failed/detected every other time regardless of fob and suspected failure in SMK (part of IBU).
They also tried a reprogram which did not work.

New one hasn't been swapped in yet but when it does I'll update this post.

Kind of sounds like the dealership diagnosis was correct!

 

[Grump]

They're pretty solid. I checked my IBU when considering mykeypremium and I have the metal bracket guarding it. Sucks to be the tech I guess.

 

[D.J.]

They're pretty solid. I checked my IBU when considering mykeypremium and I have the metal bracket guarding it. Sucks to be the tech I guess.

That metal bracket, so strange that it exists in some parts of the world only!

 

[Grump]

Replacing the IBU solved the issue. Dealer left the bracket off. My TPMS stopped working on the way home, I wonder if its related. :/ Just says drive to display. DJ, will OBD show TPMS readings before the car figures out which sensor is where?

 

[D.J.]

Replacing the IBU solved the issue. Dealer left the bracket off. My TPMS stopped working on the way home, I wonder if its related. :/ Just says drive to display. DJ, will OBD show TPMS readings before the car figures out which sensor is where?

Yes...

The car display will only show when all 4 sensors are detected.

Using an app + OBDII adapter can show each sensor as they are detected, before all 4 shows on the cars display.

 

[Grump]

Yes...

The car display will only show when all 4 sensors are detected.

Using an app + OBDII adapter can show each sensor as they are detected, before all 4 shows on the cars display.

Thanks. I'll grab an obd to see if it's the IBU or just coincidence.

 

[D.J.]

Thanks. I'll grab an obd to see if it's the IBU or just coincidence.

I forgot, I made this video 10 months ago.... Showing the TPMS sensors getting picked up, and then once all four are detected, it shows on the dash.

 

[Grump]

Tpms very intermittent since body control module changed, more broken than working. Bought a scanner, all 4 tpms came up but in the wrong positions, dash stuck on drive to display. Took it to dealer, they programmed again and it seems to be working now. OBD also shows them in the correct positions.

Dj if you open car scanner and go to programming, tpms, sensor id (#2) what does it say there for you? My current order is 8508211F, 850818BA, 85082884, 85082BBF. This changed since they fixed it. I was under the impression the car auto learned tpms locations so this doesn't make sense to have fixed values.... unless these are modules at all 4 corners to detect tpms?

 

[D.J.]

Tpms very intermittent since body control module changed, more broken than working. Bought a scanner, all 4 tpms came up but in the wrong positions, dash stuck on drive to display. Took it to dealer, they programmed again and it seems to be working now. OBD also shows them in the correct positions.

Dj if you open car scanner and go to programming, tpms, sensor id (#2) what does it say there for you? My current order is 8508211F, 850818BA, 85082884, 85082BBF. This changed since they fixed it. I was under the impression the car auto learned tpms locations so this doesn't make sense to have fixed values.... unless these are modules at all 4 corners to detect tpms?

I will check shortly,

But I can say with absolute certainty, that yes, the car does auto learn the TPMS locations.

No action is required when rotating wheels front to back or left to right or both, or even changing a single TPMS sensor.

 

[D.J.]

Tpms very intermittent since body control module changed, more broken than working. Bought a scanner, all 4 tpms came up but in the wrong positions, dash stuck on drive to display. Took it to dealer, they programmed again and it seems to be working now. OBD also shows them in the correct positions.

Dj if you open car scanner and go to programming, tpms, sensor id (#2) what does it say there for you? My current order is 8508211F, 850818BA, 85082884, 85082BBF. This changed since they fixed it. I was under the impression the car auto learned tpms locations so this doesn't make sense to have fixed values.... unless these are modules at all 4 corners to detect tpms?

I don't see "programming"..

But the closest I could manage is this.

Download Screen_Recording_20250826_164651.mp4 | LimeWire

Download Screen_Recording_20250826_164651.mp4 on LimeWire

limewire.com

Trying a new (to me) free video sharing platform.

 

[Grump]

That's the one. Thanks DJ. Must be identifiers for the tpms themselves. Guess I'll see what happens come winter tire time.

 

[D.J.]

That's the one. Thanks DJ. Must be identifiers for the tpms themselves. Guess I'll see what happens come winter tire time.

I believe that is correct.