URGENT help needed ! key fob/alarm.

[xsarahx]

I really hope someone can help me with this as its driving me nuts !!

Replaced what i thought was a flat battery in my keyfob (it has been working intermittently for a few days) Tried to open the car but it wouldnt work with the new battery in, even though the light was flashing on the key fob buttons, took the battery out and tried in my spare key fob but it was exactly the same. Took the battery back to halfords to have it tested and they said there was nothing wrong with the it.  This morning it tried open the car with the keyfob but again it wouldnt work so i unlocked the door with the key setting the alarm off straight away, tried to turn the alarm off with the fob whilst sat in the car but no joy, lights flashing but alarm still going off. Started the car up and the alarm was still going off !!

May have ONE faulty key fob but surely both of them cant be ? Is there some sort of morse code style thingy i can do to disable the alarm manually ?

Cant drive the car and my neighbours are going to kill me if i dont get it sorted !  s:evil: :evil: s:evil:

[spit]

Something that has come up before is interference from remote doorbells and such-like that screw up the fob's transmitter. Have a read here:  l viewtopic.php?f=31&t=31941 l

So before your neighbours kill you, check with them to see if they got any new toys for Christmas?  s:D s:D  

And be vigilant in case there's something more sinister going on.

[xsarahx]

Yes i have just been reading previous threads here but i would say the last 2 weeks its been happening in all different places, so i dont think anything like that is affecting it.

[mrzwei]

If the light on the key fobs comes on when you press either the lock or unlock buttons and you have a new CR1616 (or equiv.)lithium battery then that should rule out the fobs as the problem.
Operating with just the the key can't disable the alarm

[xsarahx]

Yep lights on the key are flashing when pressed and ive checked the battery and its the correct one so i guess thats not the problem,

Any more ideas what it could be ?

Looked through all my paperwork and security booklet but it doesnt say alot.   s:( s:(  

Also been all around the car pressing the buttons at various angles and pointing it at different bits inside the car but its ignoring me completly !! ............... little bugger !

[Anonymous]

Does it work in other locations?

[Nchillin75]

Hi all,

I have just had the same problem as below. 2003 Facelift MR2 Mk3.

Both fobs working fine, then this morning nothing. Fob light works suggesting battery ok, central locking and alarm won't disable. Manual entry via key sets the alarm off.

Re-programmed the key but this appears to be more to do with the immobiliser than the alarm and central locking. Car starts fine and did prior to re-program. But alarm keeps going off as long as doors are open and movement inside. In nutshell, I can't drive it.

Did anyone find a solution to this?

Figure its between the fob and the receiver on the car.

Note: Checked the microswitch to ensure the clicking sound was present indicating the microswitches are working fine but it will neither unlock or lock on both fobs.

Need help urgently!

Many thanks

Neil

[Wabbitkilla]

does it work ok away from home?
If you sit with the door open until the alarm stops sounding you should be able to start and drive the car (memory is sketchy here as it's a while since it happened to me)

[Nchillin75]

hi ya

mmm, think I tried that but as soon as I closed the door or created movement inside the alarm went off again. Engine starts but as mentioned the alarm does appear to be a separate entity to the immobiliser.

this negates the ability to drive from house to somewhere else unless I can justify the flashing lights and siren  s:) s:)

I did here mention of interference and driving it somewhere to test but I've not seen a post suggesting this actually works?

very frustrating for me and the neighbours whilst testing various theories  s:) s:)

[StuC]

Reading some other old threads, perhaps it is worth having a look at the alarm unit itself. Thread with pictures of how to locate it  here. This issue has come up a few times now.

[phils99]

you have to program the key twice (well I did when I got a new one!)

Firstly to pair with the car immobiliser to enable the key to start the car and secondly with the radio frequecies to enable the key to lock/unlock the doors and enable/disable the alarm.

Have you carried out the second programming sequence?

not sure how to attach a doc here, but if you PM me your email, I can send you the doc I used to pregram the fob buttons to work.

[Nchillin75]

Hi Stu

Many thanks - will take a look. Still figure this comes down to a transmission problem from fob to receiver. Question is, where is the receiver? By the looks of those threads the sounder is in the frunk. Assume the receiver or whatever accepts the fob transmission is located there too?
Yup I've seen a few posts on this but no fixes as such. Much like wireless I.T networks its the dark art of radio signals, they either work or they don't and figuring out why is nothing short of a miracle. Fob or receiver is going to cost and the appropriate law dictates you fix the wrong end  s:) s:)

[Nchillin75]

Hi Phil

I did re-programme my key twice but no change....is there a different method for the fob compared with the key itself?

I used the open door closed door insert key routine which was confirmed by a clunking of the locks. The key always started the engine (key to immobiliser) prior to re-programming and after but the fob would not unluck or lock the car / switch the alarm off.

Will drop you a PM. Hoping you have a different routine for the fob  s:) s:)

[phils99]

yes...the second programming gets you to press the key fob buttons after the open/close door/insert key routine.

[Nchillin75]

ah yes that was at the end of my script.

is there a defined time limit after the clunking locks confirmation?

I did try but clearly I may have mis-timed it or not followed that element accurately. What is the confirmation from the car once done? or is it that everything goes silent and the doors work once more  s:) s:)  returning me to a ridiculously happy MR2 driver

[StuC]

Hi Stu

Many thanks - will take a look. Still figure this comes down to a transmission problem from fob to receiver. Question is, where is the receiver? By the looks of those threads the sounder is in the frunk. Assume the receiver or whatever accepts the fob transmission is located there too?
Yup I've seen a few posts on this but no fixes as such. Much like wireless I.T networks its the dark art of radio signals, they either work or they don't and figuring out why is nothing short of a miracle. Fob or receiver is going to cost and the appropriate law dictates you fix the wrong end  s:) s:)

This is the unit I was talking about. I believe that it is the sensor, that's why I suggested this as a possible problem.
The siren itself, in it's stock position is under the spare wheel. Other members have moved it out of this position and located it under the frunk plastics. Just a thought whilst you are experimenting with various bits and bobs, might be to stuff a towel over the alarm to make it less noisy. So your neighbours aren't on your back as much.

Hopefully Phil's key stuff works first though.
Phil - Is it different to this stuff?

[Nchillin75]

hi, yes towel idea is an excellent plan  s:) s:)

if you inserted a link or an image in to that last post I can't see it. were you highlighting where the sensor was located?

[StuC]

hi, yes towel idea is an excellent plan  s:) s:)

if you inserted a link or an image in to that last post I can't see it. were you highlighting where the sensor was located?

There are pictures in my last post and a link in the one before.
Are you view the forum on a PC or a mobile device using tapatalk?

[Nchillin75]

Hi Stu - PC

can't see the images - got the link for the key square dance which differs ever so slightly to routine I put on for the neighbours this morning. does seem to be many variations.

2003 onwards is my specific

[StuC]

Hi Stu - PC

can't see the images - got the link for the key square dance which differs ever so slightly to routine I put on for the neighbours this morning. does seem to be many variations.

2003 onwards is my specific

Weird!   s:( s:(    s:cry: :cry: s:cry:  

 m http://i1186.photobucket.com/albums/z37 ... d047b5.jpg m

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 m http://i1186.photobucket.com/albums/z37 ... 2f360d.jpg m

Links to images above

[Anonymous]

Just a thought here, the alarm unit there is under the plastics that can fill up with water due to blocked drains etc. Could we be seeing the results of water damaged electronics by any chance?

[StuC]

Nice deduction there Meeerrrk  s;-) ;-) s;-)

[Nchillin75]

Stu - can now see - many thanks

[StuC]

Thank goodness for specsavers!  s;-) ;-) s;-)   s:lol: :lol: s:lol:

[Nchillin75]

I'd agree with the water theory, if the central locking worked but the alarm didn't or vica versa. Central locking and the alarm must be on two different circuits to a point...as both work normally but cannot be activated by the fob, suggests sensor no?

or as we possible mentioned the fob has lost its connection to the car.

question: are the key and the fob both based on the same chip? apologies I don't know how key coding works. But I would imagine as their is only one circuit board in the fob, they are the same? so if the key can be coded to the car but the fob can't, gonna have to presume the fob does work but I'm rubbish at synchronising the last section of the key coding element. i.e. the two button fob push.