Hi there

Sorry for the long delay and thanks for the information!
Yes, I am afraid when I heard the term fob from Hyundai I assumed that
it must be 'FOB' and I capitalised it for a reason I cannot explain -
apologies for that.

Thanks for the info. I will try to piece together what has been
happening for the past four months to try to establish a pattern that I
can hopefully present to the Hyundai service center when I take the car
in again on Thursday. I am going to be an annoying person who just
learnt what a BCM is but wants it checked anyway : )

The brief history I am going to give them is as follows:
The first time the RAC came out to help me I could not unlock the car
with the key fob. They thought it might have something to do with my
working near Heathrow airport - there is constant air traffic. So they
showed me how to 'fudge' the remote - holding down two buttons until
the flickering stopped and then clicking another button. After this
procedure the remote seemed to work again, until the next time.
This happened twice at work so I assumed it must be the proximity to
the airport but then it happened outside my house and since then just
about anywhere - no airplane needed.

One particularly cold morning the remote just seemed totally dead. So I
changed the batteries and then needed to use the fudge again to get the
car open. Did not work that time and once again the RAC people came out
and after several attempts we managed to get the car open (fudge
finally kicked in).

Since then I have taken the car into the service center in preparation
for the drive up to Edinburgh. They said that they changed the
batteries in one of the fobs and replaced the other fob. Both worked
when I left there but within 3 days the old fob developed a sticky
button and I had to remove the batteries (green light came on and I
just could not shut it down). That killed any comfort feeling and I
could not get a booking at the service center that close to Christmas.

The second fob failed in Edinburgh just before we were meant to drive
down. We called RAC out again and the guy really battled to get the car
opened but the fudge finally worked after about half an hour of trying.
Both fobs are now dead - both seem to have problems which is strange.

I like the car a lot but this is seriously stressing me out and I
really hope I have some good news on Thursday.

 

Hi there

Sorry for the long delay and thanks for the information!
Yes, I am afraid when I heard the term fob from Hyundai I assumed that
it must be 'FOB' and I capitalised it for a reason I cannot explain -
apologies for that.

Thanks for the info. I will try to piece together what has been
happening for the past four months to try to establish a pattern that I
can hopefully present to the Hyundai service center when I take the car
in again on Thursday. I am going to be an annoying person who just
learnt what a BCM is but wants it checked anyway : )

The brief history I am going to give them is as follows:
The first time the RAC came out to help me I could not unlock the car
with the key fob. They thought it might have something to do with my
working near Heathrow airport - there is constant air traffic. So they
showed me how to 'fudge' the remote - holding down two buttons until
the flickering stopped and then clicking another button. After this
procedure the remote seemed to work again, until the next time.
This happened twice at work so I assumed it must be the proximity to
the airport but then it happened outside my house and since then just
about anywhere - no airplane needed.

One particularly cold morning the remote just seemed totally dead. So I
changed the batteries and then needed to use the fudge again to get the
car open. Did not work that time and once again the RAC people came out
and after several attempts we managed to get the car open (fudge
finally kicked in).

Since then I have taken the car into the service center in preparation
for the drive up to Edinburgh. They said that they changed the
batteries in one of the fobs and replaced the other fob. Both worked
when I left there but within 3 days the old fob developed a sticky
button and I had to remove the batteries (green light came on and I
just could not shut it down). That killed any comfort feeling and I
could not get a booking at the service center that close to Christmas.

The second fob failed in Edinburgh just before we were meant to drive
down. We called RAC out again and the guy really battled to get the car
opened but the fudge finally worked after about half an hour of trying.
Both fobs are now dead - both seem to have problems which is strange.

I like the car a lot but this is seriously stressing me out and I
really hope I have some good news on Thursday.

 

It sounds as if your fobs may be different than those in the U.S. Do you
have a key lock, or must you unlock by transmitter only?

As far as interference, it's quite possible. The radio frequencies these
systems operate on in the U.S. are actually allocated to military. If
we're particularly near a military installation, car remotes, garage door
openers, and many items don't work intermittently. In fact, many radio
transmissions, if strong enough, can cause interference.

Your remotes may be rolling-code type. I don't believe Hyundai uses those
in the U.S., but other manufacturers do. It is possible in that case for
the transmitter to become unsynchronized with the receiver in the car.
The fudge method you describe sounds like the typical method for
resynchronization of rolling code transmitters.

It sounds to me like the repair facility there is on the right track. If
replacing the transmitter or transmitter battery solves the issue, then I
suspect the issue was present and clear at the time of servicing. If you
indeed have the rolling code type transmitters, then that would
significantly reduce the probability of a BCM error causing
unsynchronization. In fact, I believe the synchronization is not retained
in BCM if battery power is disconnected (presuming your system to be
similar to others of the rolling code type I've seen).

 

It sounds as if your fobs may be different than those in the U.S. Do you
have a key lock, or must you unlock by transmitter only?

As far as interference, it's quite possible. The radio frequencies these
systems operate on in the U.S. are actually allocated to military. If
we're particularly near a military installation, car remotes, garage door
openers, and many items don't work intermittently. In fact, many radio
transmissions, if strong enough, can cause interference.

Your remotes may be rolling-code type. I don't believe Hyundai uses those
in the U.S., but other manufacturers do. It is possible in that case for
the transmitter to become unsynchronized with the receiver in the car.
The fudge method you describe sounds like the typical method for
resynchronization of rolling code transmitters.

It sounds to me like the repair facility there is on the right track. If
replacing the transmitter or transmitter battery solves the issue, then I
suspect the issue was present and clear at the time of servicing. If you
indeed have the rolling code type transmitters, then that would
significantly reduce the probability of a BCM error causing
unsynchronization. In fact, I believe the synchronization is not retained
in BCM if battery power is disconnected (presuming your system to be
similar to others of the rolling code type I've seen).

 

The remote disables the alarm and unlocks the doors. Using just the key
I can unlock the doors but not enable the alarm.
I read up briefly on this rolling code type alarm and it sounds like a
great idea in theory. The problem with the fudge is the remotes don't
seem to be up to the job. The buttons stick and they seem to drain the
batteries remarkably fast (althought I guess what could be happening is
the button is depressed in my coat pocket, sticks and then runs down
the batteries that way).

If this is a rolling code type of remote I am guessing that the device
in the remote that syncs the codes with the matching device attached to
the car is not easy to change? I guess what I need to know is what
options do I have? Am I just doomed never to use my alarm system again
(overly dramatic, maybe : )

 

The remote disables the alarm and unlocks the doors. Using just the key
I can unlock the doors but not enable the alarm.
I read up briefly on this rolling code type alarm and it sounds like a
great idea in theory. The problem with the fudge is the remotes don't
seem to be up to the job. The buttons stick and they seem to drain the
batteries remarkably fast (althought I guess what could be happening is
the button is depressed in my coat pocket, sticks and then runs down
the batteries that way).

If this is a rolling code type of remote I am guessing that the device
in the remote that syncs the codes with the matching device attached to
the car is not easy to change? I guess what I need to know is what
options do I have? Am I just doomed never to use my alarm system again
(overly dramatic, maybe : )

 

If this car is similar to those in the U.S., you may be able to disarm the
alarm using an alternative method as follows:

1. Open the door with the key. In the U.S., the alarm will sound.
2. Get in the vehicle. Turn the key to the "start" position and release
to the "on" position (just like you would if you had actually started the
vehicle).
3. Wait 30 seconds. The alarm will stop sounding before then, but you
must wait 30 seconds.
4. After 30 seconds, try again to start the vehicle. It should start.

Also, if you don't lock the vehicle with the remote, the security system
will not arm.

 

If this car is similar to those in the U.S., you may be able to disarm the
alarm using an alternative method as follows:

1. Open the door with the key. In the U.S., the alarm will sound.
2. Get in the vehicle. Turn the key to the "start" position and release
to the "on" position (just like you would if you had actually started the
vehicle).
3. Wait 30 seconds. The alarm will stop sounding before then, but you
must wait 30 seconds.
4. After 30 seconds, try again to start the vehicle. It should start.

Also, if you don't lock the vehicle with the remote, the security system
will not arm.

 

I am ecstatic!! This morning I took my car in for the routine fob
replacement and while I was there I asked about replacing the alarm
system. A very helpful man said he would look into it and minutes later
they contacted me to say they would be able to do it!!

I picked up the coupe this evening with two totally different new fobs
and they work and the range has dramatically increased (it now rivals
my husbands Smart). Stress testing still needs to be conducted
(although I must have tried it about 10 times already today) but they
have restored my faith and I am feeling hugely grateful to the center
that helped me. I will be writing to them to say as much.

And thank you for all the information and for taking the time to
explain things to me. It is much appreciated.

And for completeness: On your suggestion above one of the guys from the
RAC tried it and what happens is that the car starts but then the alarm
sounds and then stops after so many seconds and continues in this
fashion. I am not sure if you could drive the car as presumably the
immobiliser is disabled by the key but the alarm kept sounding.

 

I am ecstatic!! This morning I took my car in for the routine fob
replacement and while I was there I asked about replacing the alarm
system. A very helpful man said he would look into it and minutes later
they contacted me to say they would be able to do it!!

I picked up the coupe this evening with two totally different new fobs
and they work and the range has dramatically increased (it now rivals
my husbands Smart). Stress testing still needs to be conducted
(although I must have tried it about 10 times already today) but they
have restored my faith and I am feeling hugely grateful to the center
that helped me. I will be writing to them to say as much.

And thank you for all the information and for taking the time to
explain things to me. It is much appreciated.

And for completeness: On your suggestion above one of the guys from the
RAC tried it and what happens is that the car starts but then the alarm
sounds and then stops after so many seconds and continues in this
fashion. I am not sure if you could drive the car as presumably the
immobiliser is disabled by the key but the alarm kept sounding.