Can you open the tail gate without using the remote?
If so, I would say the your are having issues with the interior antenna.


If not, then, probably the module is having issues when getting the signal from the antennas.


Good luck, and please let us know if you find the cause of the problem.

 

When you say the batteries in the keys are okay, what does that mean exactly? Are they newly replaced? Did you test the voltage?

Most likely the proximity frequency output that activates the little black door button is different than that of the push button outputs, so if both batteries are indeed "known good," then I am more inclined to think it is on the receiver side, in the antenna assembly or wherever the receiver circuitry itself is located (I believe that may be in the push-button start switch), that isolates the proximity key frequencies, but don't quote me on this.

 

Rear hatch does not unlock without using fob unlock button, no doors open by proximity sensor.
Both fob batteries are new and just tested as good, no issues with fob batteries.
As stated key not recognised once in car either.

 

Thanks for replying back.


IMHO, the problem would be the module.


2 Key fobs and/or all the antennas are broken? it's hard to believe!

1. Buzzer
2. RF receiver
3. Smart key unit
4. Interior antenna 1
5. Interior antenna 2
6. Interior antenna 3
7. Bumper antenna

 

I know this is an old Thread but thought I would ask here first. I am having a similar situation as OP.
Car does not recognise that our FOBs are in proximity except for the tailgate. The tailgate will open without issue if the FOB is close enough.
The doors will not, the engine does not recognise it and the buttons do not work.
I have had multiple mechanics and auto electricians look at it but no one has been able to fix it.
Any ideas?

Also, does anyone know where the interior antennas are located on a 2010 ix35? and how many there are? because I feel like because the tailgate is recognising the FOB it could be something to do with the other antennas but I find it hard to believe that all but 1 broke at the same time.

Thank for any insight you might have.

 

I’m having the same issue with my 2010 model. The passive unlock/lock and start functionality does not work. I get a “key is not detected” error. I can still use the buttons on the remotes to lock/unlock and I have to insert the key into the centre console to start the car.

 

I have the same issue with my 2010 ix35, totally stumped as to what fails but I find that if a disconnect the battery for 24 hours all will work O.K for the next couple of days, then fails again!
So confused by this and the local Hyundai garage failure to fault find I have written to Hyundai H.Q regarding this. Can anyone tell me where the module is located so that I can inform our local Hyundai garage, for they can't find it!!!!!!!

 

Snap! I’ve not disconnected the battery for 24 hours, but I did for 1 hour and it didn’t make a difference. Does yours still lock/unlock with the fob buttons and start with the key in the fob holder?

I paid £79 for my local Hyundai dealer to “diagnose” the fault - they didn’t really do that. They thought it “could” be a grounded wire above the headliner and then wanted £350 to remove my headliner. I obviously refused as there was no guarantee it was the issue.

 

'Does yours still lock/unlock with the fob buttons and start with the key in the fob holder?' The answer is yes, key fob operation is unaffected but have to use the central armrest socket to start. The electrical system has a built in capacitor so battery needs to be disconnected for over an hour to clear it. This indicates to me that we may be dealing with an ECU issue here?
As I stated I have now written to Hyundai H.Q for help with this, will they respond????

 

'Does yours still lock/unlock with the fob buttons and start with the key in the fob holder?' The answer is yes, key fob operation is unaffected but have to use the central armrest socket to start. The electrical system has a built in capacitor so battery needs to be disconnected for over an hour to clear it. This indicates to me that we may be dealing with an ECU issue here?
As I stated I have now written to Hyundai H.Q for help with this, will they respond????

Could you let me know what Hyundai say? My local garage did say the grounding wire above the headliner is a “common” fault, is it just coincidental ours are both 2010 built with the same fault?

I might see if mine works after the battery being disconnected for longer. A couple of strange behaviours mine also exhibits:

• If I remove the key from holder after starting the engine it will let me keep driving without any warnings / errors.
• If I turn off the engine, leave the key in the fob holder, close the doors and try to lock the car via the handle buttons it gives me an audible warning.

The smart key module is located behind trim panels in the passenger footwell I believe.

 

O.K, first I believe the socket only allows the ignition to connect, as does the normal keyless start once the fob is recognised. I remove mine once started the car is started and put it in my pocket as normal.
Secondly the system won't allow you to lock the car with the fob inside so this must be an independent system connected to the alarm system. For as we know the keyless system doesn't work. Still scratching my head over that one but at least it still works.
Thanks for the info on possible module location. I have a very good local garage (not Hyundai) and may ask them to see if they can find it.

 

O.K, first I believe the socket only allows the ignition to connect, as does the normal keyless start once the fob is recognised. I remove mine once started the car is started and put it in my pocket as normal

Do you not find it strange the car will let you continue to drive without a detected key? Surely our car's engine start behaviour should be:
1) Can't detect smart key, warn user. Request key inserted
2) Read key, start engine
3) User removes key from fob holder, car scans interior for smart key
4) Smart key not detected (our systems are faulty) warn 'KEY OUT'

It just seems wrong that my car lets me drive when it can't 'see' a key!

Secondly the system won't allow you to lock the car with the fob inside so this must be an independent system connected to the alarm system. For as we know the keyless system doesn't work. Still scratching my head over that one but at least it still works.

I used this to test my door handles, although a basic test. The car gives me an audible warning if I've leave the fob in the holder and press the driver/pax door button in an attempt to lock it. This tells me the door buttons are at least semi-functional.

Thanks for the info on possible module location. I have a very good local garage (not Hyundai) and may ask them to see if they can find it.

You'll probably find these helpful:

Smart key system module locations:

Smart Key ECU "wiki":

Smart Key ECU wiring diagram:

I have 1-2 garages in my area that I trust, but none seem willing to assist with this issue hence why I took it back to a Hyundai dealer. I thought their diagnostic software would be able to interrogate and test each component of the keyless system to pin point where the issue is. Based on my experience that's not the case!

 

This is what the Hyundai diagnostic software can do to test the system:

Antenna Actuation test

Antenna status check:

And also the following:

• Serial Communication Status Check
• Interior Antenna Actuation Check
• FOB Status Check
• Smart Key Status Check
• PDM Status Check
• Neutralization Status Check

 

Fabulous amount of information, many thanks. I have a full understanding of the setup now, all I need is a garage that will test the system as obviously my local dealer didn't (or did but decided to charge me the earth by saying that they would have to remove most of the interior to find the unit).
So the key-less ECU is independent from the main ECU but would still hard reset when you pull the battery. My guess is that one of the sensors is sending rouge data to the unit which is causing a system freeze, as what can happen in a computer, phone or tablet you may own. If things lock up the first option is always turn in off and back on again! Many thanks, will keep you informed.

 

Look what just came up on a Hyundai Facebook page: Facebook Groups

Another 2010 models keyless entry has stopped working. This is more than just a coincidence! The system seems to self destruct after 9/10 years. Clearly this a common fault.

 

Clearly, let's see if I get a response from Hyundai?

 

I suspect it'll be a fob-off response saying your warranty has expired. Let's hope I'm proven wrong!

I've disconnected the negative cable on my battery. I'll leave it for 24 hours and see if that resets the keyless system like on yours

Do you mind me asking where you're based? I'm in Hertfordshire.

 

Maidstone, Kent.

Had the battery off again, only 12 hours, strange reset, sometimes it's working and others not.

I'm going to get to the bottom of this, something is causing a code error. Now I know the location of the receivers I'm going to see if I can isolate each one (if I can get at them). I can buy a secondhand module on e-bay for £28 but I need to find out a fitting cost as the glove compartment needs coming out. 😏

I can dismantle & build computers but not dashboards. 🤭

 

Maidstone, Kent.

Had the battery off again, only 12 hours, strange reset, sometimes it's working and others not.

I'm going to get to the bottom of this, something is causing a code error. Now I know the location of the receivers I'm going to see if I can isolate each one (if I can get at them). I can buy a secondhand module on e-bay for £28 but I need to find out a fitting cost as the glove compartment needs coming out. 😏

I can dismantle & build computers but not dashboards. 🤭

Did it start working again after the 12 hour battery disconnect? I assume you only remove the negative too? I’m going to leave mine disconnected until I need to use it tomorrow afternoon. Can I check your trip computer completely resets too?

Although the module can be purchased second hand I have heard from reputable sources that it will need programming to the car as it’s linked to the alarm and ignition system. If it is the module malfunctioning another local Hyundai garage quoted me £2,000 for replacement! I’m not sure how much of that was labour.

I’m not glad you’re also suffering the same issue but it’s somewhat reassuring that it appears to be a common fault rather than one isolated to my car.

 

Yes all data other than trip A & B and total mileage is reset. Think this has to be recorded in a separate file for legal reasons.
Normally only neg terminal but at times both + &. -. Does seem to make much difference.
And yes the thought crossed my mind re: programming the keys & alarm. 😕

I was quoted £1600 to replace completely but they wouldn't guarantee it curing the issue!!!!!

 

So I just re-connected my battery, the negative has been disconnected since 14:00 yesterday. I disconnected the positive for 5 minutes as well just to be safe. The keyless still isn’t working, but interestingly, my trip computer hasn’t reset? It’s still got my average MPG and current trip information. My car head unit has reset however. What does this mean?

 

I thought I had a problem! What do you mean by 'car head unit'?
Seems like the ECU is still powered, but how?
Stumped!

 

I thought I had a problem! What do you mean by 'car head unit'?
Seems like the ECU is still powered, but how?
Stumped!

My stereo. It reset back to factory.

 

Really? Disconnect the battery doesn't affect my radio at all, which I've found quite strange.
So does the ix35 have 2 power sources?

 

I do have a aftermarket stereo installed, not sure if that makes a difference RE: reset.

I’m so baffled as to how my trip computer retained its info after being disconnected for nearly 24 hours. I’ve never known a car do this. I’m wondering whether this means I have a bad circuit somewhere, but where would the power come from?

 

The mileage and trip do not reset but everything else does, average mpg, engine hours, service data etc. Well it does on mine.

Following recent reset I am NOT using keyless entry, only key fob. To date car starting keyless each time... but don't hold your breath!

 

Ah, ok! Mine has reset in that case, I thought it would all reset.

 

Hi @RayJC . Any news on your keyless system? I’ve not had any further diagnostics on mine (yet!)

 

Hi, sorry about delay in responding, I thought my last reply had been posted but just realised it hadn't.

I have today received a response to my letter from customer services to which I have replied. Email me on me14@blueyonder.co.uk and I'll let you have copies.

In the meantime I have whittled it down to a possible fault in the passenger door button sensor. As long as I use the key fob to unlock I can start keyless. Also if a passenger gets in and the key alarm screams the keyless start will fail. Disconnect battery for a couple of hours to reset.

 

Can anyone provide me with a wiring diagram for the following:
A) keyless module
B) Sunroof

I think my issue may be broken wiring above the headliner (as suggested by Hyundai) due to the fact I don’t get a audible warning if I leave the sunroof open and lock the car, which it should. This suggests to me the wire that sends the open/closed signal to the locking system may be damaged too! If this open/close wire is close to any wire relating to the smart key locking then I think I’ll start removing the headlining to investigate

 

Hope get to the bottom of your fault, as to mine, still using the key fob locking not the door button and still starting keyless. Seems my issue is with the door button circuit.
Have a good Xmas and a better New Year my friend.

 

So I caved and ordered this:

It arrived on Saturday but I’ve not had had a chance to really use it as I’ve been working. I plugged it into the car to see if it actually worked and it does appear to. Any tips on how I can best diagnose what’s causing the keyless not to work? I get the impression I can see / record all the keyless module signals (if any) which should indicate where the weak link is.

 

I would go to live data and check the status. Select SMK as the system in the menu and then you get options across the top.(preparation/diagnosis/vehicle S/W management/Repair.
For any programming you'll need the security code for the car. I would not mess with any restes/relearns etc in programming, likely you need the code but I don't remember now. I'm only a novice.You'll also get manuals amongst that and DTC electrical diagrams etc.

 

Well I've had a little tinker this morning and ran all the tests that were available with the following results:

• When I run the actuation test on all the antennas the result comes back "success"

I then tried the test on the antennas. GDS will tell you where to place the fob in the car so it's near the applicable antenna. For every antenna I get "test failure !!!":

I then went to the "Diagnosis" section of GDS where it allows me to view the current data from various sensors and they all appear to be 'normal' to my (very) untrained eye, with the exception of the doors being the wrong way around, eg:

• When I press the drivers door button it the "assist door" handle sensor changes from off to on
• When I press the passenger door button the "driver door" handle sensor changes from off to on

Everything else seems normal:

• External buzzer changes from "off" to "on" when I activate it
• Immobilizer indicator changes from "off" to "on" when it's illuminated
• Start/Stop button changes from "off" to "on" when I press it
• When the vehicle is locked the "SMK Power Mode State" is reported as "Off Lock".

So it looks like the cars system is working ok (?) the antennas are just not finding the keys.
1) Could it be all my antennas faulty?
2) Both my keys proximity function is broken? I've swapped their batteries 3 times (Duracell and Energiser brands) already!

 

I've updated my own thread here but I thought I would post here too. I've been digging through the GDS manual and I've noticed a few other things:

• I'm missing the "Key out indicator lamp" input switch as a option to test which I should have (image taken from GDS manual):

View attachment 453967

• The sunroof schematics shows a key in/out signal. I think this is the wire my Hyundai dealer thought could be damaged and wanted to inspect

View attachment 453966

• I think my my antenna actuation "success" results are actually false. When reading the manual it states:

  4. If the LED of smart key is blinking, the smart key is normal."

  The LED on my key doesn't blink, suggesting it's not receiving/sending anything as it should. I get "success" even if I leave the key in the house! I have swapped both key batteries three times, all with high quality (Duracell, Energiser, Varta) batteries. The fob buttons operate from long range and the LED blinks when I press them so I'm incredibly confident the fob / batteries aren't at fault.

View attachment 453965

 

I think my my antenna actuation "success" results are actually false. When reading the manual it states: The LED on my key doesn't blink, suggesting it's not receiving/sending anything as it should. I get "success" even if I leave the key in the house! I have swapped both key batteries three times, all with high quality (Duracell, Energiser, Varta) batteries. The fob buttons operate from long range and the LED blinks when I press them so I'm incredibly confident the fob / batteries aren't at fault.

I have 4 button type and the holder in the console.

Success means the command was sent. The result is what you observe. No blinky blinky red light = fail My led was blinking and I used antenna 2 with the fob on the lid

I tried the serial comms check and it was profoundly uneventful. I still think it's worth having a look at the receiver and /or reseating the connectors. Nothing to lose.

 

Did y'all ever find the answer why Smart key was not recognizing the fob? I have all same symptoms. 2011 Hyundai Sonata
lauraroyal2001@yahoo.com