How can you disable the alarm

Hi All
I have a discovery 300 TDI ES and the alarm keeps going off on it with no visable reason. The ECU module is an AMR2109 which apparently does the central locking as well (this does not work). I have both of the key fobs and pressing these does not turn the alarm off. Is it just a case of disconencting the AMR2109 to bypass the alarm or will this cause further issues? Any help would be greatly appreciated as it just wont shut up.
Thanks

Not being funny, but the above scenario sounds exactly like the symptoms you'd get if you just nicked a Discovery 300TDI.

Convince us you're the genuine owner (eg offer an explanation as to why the key fob doesn't work....) and I'll tell you how to bypass the alarm really quick.

Two things that go faulty and set off the alarm, the interior ultra-sonic sensor and bonnet switch unplug these one at a time and see if it helps, also with single button fobs you can DIY reprogram them that may get them working and also fit new batteries as well.
The vehicle has a immobilising system that's part of the alarm ecu so you will have a bit of wiring to do so your engine will start if you remove the ecu.
There's loads of info in the forum and on the web already if u search for it.

And :welcome2: to the Forum

Hi.

Ive have just come to my 300tdi and the immobiliser won't disengage, both key fobs have stopped working and when I unlock the drivers door with the key it sets the alarm off. When I try ignition it does nothing.

I have removed the ecu 2109 and found that its got/had water ingress so its very snotty on the bottom of the PCB. I have ordered another ecu from fleabay but would love to know a bypass to use as a workaround until this arrives.....

I understand that this is pretty sensitive information so a PM with bypass info would be very much appreciated, especially by Mrs Grasshopper who will be carless if the disco stays stranded not the drive.

Many Thanks

Mike

Just enter your four digit emergency access code via the drivers door lock to temporarily override the security/immobiliser system.

discool said:

Just enter your four digit emergency access code via the drivers door lock to temporarily override the security/immobiliser system.

Click to expand...

I rang my local Landrover dealer for this code and because my alarm is the older type (single button fob) it doesn't have the code. Guy said only the 2 button systems have this code

You have a 95MY disco then, so you now need to provide a temp 12v supply to two places, there's a thread or two on how to do that for Diesel engines already in the forum.

discool said:

You have a 95MY disco then, so you now need to provide a temp 12v supply to two places, there's a thread or two on how to do that for Diesel engines already in the forum.

Click to expand...

Any chance you can point me in the right direct pal? Ive tried the search function and its not coming up with anything other than the spider bypass option.....

Thanks for your help

You can bypass the immobiliser by doin the spider plug or send power from ignition to the fuel solenoid and the starter relay. Ive dun this as mine left me stranded. It is easy to do.

Theres various threads in alarm removals in search engine on here. Thats how i did it

Thanks Haigy.

Ive just got in from trying the old ECU now its been disconnected for a few hours. Connected it and tried starting, no joy. I then did a random key lock and unlock sequence in the drivers door (maybe lock, unlock, lock, unlock) and I noticed the dash LED was then lit constantly rather than flashing. Put key in ignition and hey presto the old girl sprang into life.

Ill definitely be fitting the new ECU when it arrives and will just use the key to lock and unlock from now on, I guess I was just lucky that it broke down outside my house where I have wifi and brew materials

I will definitely get a procedure for putting the links in printed out and in the car so if she does throw her hand in whilst in the middle of nowhere I can frig it to get home.

I was also thinking about putting the links in permanently and putting a hidden switch somewhere so I can switch on the immobiliser when required...

Thanks for taking the time to reply, much appreciated.
Mike

As u have an active immobiliser as apposed to the passive two button system, u may have had a sticking micro switch permantly signalling to immobilise hence the fob not working, so by using the key in door lock to operate the micro switch may got the switch operating correctly.
So if u have a similar issue in the future the switch may be worth checking, micro switches have been known to fail.

discool said:

As u have an active immobiliser as apposed to the passive two button system, u may have had a sticking micro switch permantly signalling to immobilise hence the fob not working, so by using the key in door lock to operate the micro switch may got the switch operating correctly.
So if u have a similar issue in the future the switch may be worth checking, micro switches have been known to fail.

Click to expand...

Thanks Discool. Where are the micro switches? In the drivers door?

For info, Ive had the car a couple of months and always used the key until a couple of weeks ago when I put a new spring in the drivers door, I have been using the fob since then....

Out of interest, will I have a spider unit or is my car too early? Is there any way to tell without taking the dash out and physically looking?
Thanks again

First the micro switch is near the lock barrel and operate by cam that turns with the key, the cam is plastic so can sometimes break. There's a second micro switch, that is for alarm/ central locking in the same location. Just follow the cable to locate the exact positions.

You don't have a spider, unless your system had a two button fob, the passive system with the spider was introduced with the 1996MY disco.

Also don't forget that if your using your existing fobs with a replacement control unit they will have to be reprogrammed to match, this function is DIY and info on that is also in the Forums.

discool said:

First the micro switch is near the lock barrel and operate by cam that turns with the key, the cam is plastic so can sometimes break. There's a second micro switch, that is for alarm/ central locking in the same location. Just follow the cable to locate the exact positions.

You don't have a spider, unless your system had a two button fob, the passive system with the spider was introduced with the 1996MY disco.

Also don't forget that if your using your existing fobs with a replacement control unit they will have to be reprogrammed to match, this function is DIY and info on that is also in the Forums.

Click to expand...

Brilliant thanks.

I just wanted to be sure that replacing the ECU will likely sort the problem, hopefully saving the worry every time I unlock it wondering if she will start.

Ive seen the fob programming procedure, I tried to do it before I removed the ECU but it didn't do anything. Hopefully once a fully working ECU is installed the fobs will program as per the destructions on here.

Again, thanks for all your advise. Big welding job starting tomorrow now I can (hopefully) get her moving to my mates barn. She needs 2 new front arches and some patches on the inner sills towards the back.

All needs doing before the MOT deadline next Wednesday, nothing like leaving things tip the last minute hey......

Mike