weak keyless entry-2004 Sonata LX
 

Lately sometimes when I hit the unlock button on the keyless entry
remote, I hear only a weak "thunk" and the doors remain locked. Normally
there's a loud "Thunk" and the doors are unlocked. I tried the other new
unused remote and it acts the same. Trip to Hyundai dealer? new remote
batteries?

Re: weak keyless entry-2004 Sonata LX
 

Bob wrote:
> Lately sometimes when I hit the unlock button on the keyless entry
> remote, I hear only a weak "thunk" and the doors remain locked. Normally
> there's a loud "Thunk" and the doors are unlocked. I tried the other new
> unused remote and it acts the same. Trip to Hyundai dealer? new remote
> batteries?

If you hear the locks as you do, it indicates that the remote is working
fine. It's only a transmitter and the car either receives the signal or
it doesn't. If you press the unlock button more than once, as necessary
to unlock all the doors, do any of them unlock? If not, The problem may
be the battery in the car or a bad electrical connection or ground. If
only the driver's door fails to unlock, it's likely the actuator in that
door.

Re: weak keyless entry-2004 Sonata LX
 

Brian Nystrom wrote:
> Bob wrote:
>
>> Lately sometimes when I hit the unlock button on the keyless entry
>> remote, I hear only a weak "thunk" and the doors remain locked.
>> Normally there's a loud "Thunk" and the doors are unlocked. I tried
>> the other new unused remote and it acts the same. Trip to Hyundai
>> dealer? new remote batteries?
>
>
> If you hear the locks as you do, it indicates that the remote is working
> fine. It's only a transmitter and the car either receives the signal or
> it doesn't. If you press the unlock button more than once, as necessary
> to unlock all the doors, do any of them unlock? If not, The problem may
> be the battery in the car or a bad electrical connection or ground. If
> only the driver's door fails to unlock, it's likely the actuator in that
> door.

Thanks Brian. Your logic makes sense that the remote itself is good. My
remote doesn't work that way, it unlocks all the doors when you press it
once. Where is the receiver located in the car? Guess I could check
for bad grounds, etc.

Re: weak keyless entry-2004 Sonata LX
 

Bob wrote:
> Brian Nystrom wrote:
>
>> Bob wrote:
>>
>>> Lately sometimes when I hit the unlock button on the keyless entry
>>> remote, I hear only a weak "thunk" and the doors remain locked.
>>> Normally there's a loud "Thunk" and the doors are unlocked. I tried
>>> the other new unused remote and it acts the same. Trip to Hyundai
>>> dealer? new remote batteries?
>>
>>
>>
>> If you hear the locks as you do, it indicates that the remote is
>> working fine. It's only a transmitter and the car either receives the
>> signal or it doesn't. If you press the unlock button more than once,
>> as necessary to unlock all the doors, do any of them unlock? If not,
>> The problem may be the battery in the car or a bad electrical
>> connection or ground. If only the driver's door fails to unlock, it's
>> likely the actuator in that door.
>
>
> Thanks Brian. Your logic makes sense that the remote itself is good. My
> remote doesn't work that way, it unlocks all the doors when you press it
> once. Where is the receiver located in the car? Guess I could check
> for bad grounds, etc.

The issue isn't likely to be the receiver either, since you can hear the
doors attempting to unlock. If there's a bad power or ground connection,
it must be in the actuating system. Since none of the doors unlock, it
seems like it must be a main connection of some sort or perhaps a bad
relay. You can view the electrical diagrams of the system on Hyundai's
WebTech site: http://www.hmaservice.com

Re: weak keyless entry-2004 Sonata LX
 

Brian Nystrom wrote:
> Bob wrote:
>
>> Brian Nystrom wrote:
>>
>>> Bob wrote:
>>>
>>>> Lately sometimes when I hit the unlock button on the keyless entry
>>>> remote, I hear only a weak "thunk" and the doors remain locked.
>>>> Normally there's a loud "Thunk" and the doors are unlocked. I tried
>>>> the other new unused remote and it acts the same. Trip to Hyundai
>>>> dealer? new remote batteries?
>>>
>>>
>>>
>>>
>>> If you hear the locks as you do, it indicates that the remote is
>>> working fine. It's only a transmitter and the car either receives the
>>> signal or it doesn't. If you press the unlock button more than once,
>>> as necessary to unlock all the doors, do any of them unlock? If not,
>>> The problem may be the battery in the car or a bad electrical
>>> connection or ground. If only the driver's door fails to unlock, it's
>>> likely the actuator in that door.
>>
>>
>>
>> Thanks Brian. Your logic makes sense that the remote itself is good.
>> My remote doesn't work that way, it unlocks all the doors when you
>> press it once. Where is the receiver located in the car? Guess I
>> could check for bad grounds, etc.
>
>
> The issue isn't likely to be the receiver either, since you can hear the
> doors attempting to unlock. If there's a bad power or ground connection,
> it must be in the actuating system. Since none of the doors unlock, it
> seems like it must be a main connection of some sort or perhaps a bad
> relay. You can view the electrical diagrams of the system on Hyundai's
> WebTech site: http://www.hmaservice.com

Thanks for the good advice on troubleshooting my intermittent "weak"
keyless entry. It's been working normally for a few days now so I guess
maybe it fixed itself...for a while anyway. If it acts up again I'll
check some of the things you suggested.