Z3 - alarmed whilst the hood is down !!!!!!!

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ARoosterinaRoadster
Joined: Thu 29 May, 2014 08:49
Posts: 349

  Z3 roadster 2.0
Location: Lancashire

Z3 - alarmed whilst the hood is down !!!!!!!

Post by ARoosterinaRoadster »

Hi to you all out there. I have looked into the knowledge base but cannot find anything that points to an answer.

I believe that I have read somewhere that the car is alarmed when the hood is dropped insomuch as "Low-Lifes" deciding to exercise their light fingers would trigger the spacial sensors BUT the other day I decided to investigate the probability and mine will not/did not alarm the cabin area of the car.

The Owner Handbook/Manual appears not to cover the eventuallity of hood down security.

What say you !!!!!!!!!!!!!!
Happiness is a well kept Z3 and preferably running with the hood down - weather permitting.
Fender2004
Joined: Fri 14 Aug, 2009 10:24
Posts: 907

  Z3 roadster 2.8
Location: Houghton-Le-Spring

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Fender2004 »

On my car there are two sencers one at the top left and top right of the windscreen, so the alarm covers the cab area. The little Red led on your dash is a switch if you push it in it turns them off, and if the switch is in the out position they are active with the alarm.
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ARoosterinaRoadster
Joined: Thu 29 May, 2014 08:49
Posts: 349

  Z3 roadster 2.0
Location: Lancashire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by ARoosterinaRoadster »

Fender2004 wrote:On my car there are two sencers one at the top left and top right of the windscreen, so the alarm covers the cab area. The little Red led on your dash is a switch if you push it in it turns them off, and if the switch is in the out position they are active with the alarm.
Hi Fender2004. Thank you,I will go out there and investigate after evening meal.
Happiness is a well kept Z3 and preferably running with the hood down - weather permitting.
ARoosterinaRoadster
Joined: Thu 29 May, 2014 08:49
Posts: 349

  Z3 roadster 2.0
Location: Lancashire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by ARoosterinaRoadster »

Hi again Fender2004. Well now then. Where I believe that you have an LED - at the front central part of the flat curve of the dashboard - I only have a flat disc that looks suspiciously like a blanking disc and there are no Sensors at the top Left & Right of the windscreen.

The absence of the neccesary is confirmed when sitting in the car - Hood up - car alarmed and arms waving around and total silence.

My car is a 2000 (W) reg. Build date December 1999 2.0 Auto.
Happiness is a well kept Z3 and preferably running with the hood down - weather permitting.
littlefeller
Joined: Sun 28 Apr, 2013 18:06
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Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by littlefeller »

I have motion sensors too, 98 build. don't know if they work though as I have never set the alarm :shock: its not really a good idea to mess around with alarms with immobilisers on second hand cars, some will disagree but I speak from experience (not mine but a work mate and his second hand bike). unless you tested these devices before you actually brought the car, something I always forget to do :dunce: sound as though someone removed yours unless they were optional when new, sure someone here will know.
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BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
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  Z3 roadster 1.9

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by BladeRunner919 »

littlefeller wrote:I have motion sensors too, 98 build. don't know if they work though as I have never set the alarm :shock: its not really a good idea to mess around with alarms with immobilisers on second hand cars, some will disagree but I speak from experience
The alarm and immobiliser are different systems on the Z3, so you won't really cause any problems by messing about with the alarm. And, unless you have an EWS delete, you can't avoid using the immobiliser.
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Robert T
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  Z3 roadster 1.9
Location: Cheshire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Robert T »

The early alarm (separate fob type) has a pushable LED and the movement sensors are visible at the top of the windscreen pillars. Pushing the button disables the movement sensors.

The later alarm (buttons on the key) just has an LED light and the sensors are hidden in the footwells. Locking the car twice with the remote disables the movement and tilt sensors.

On neither alarm is there anything that detects whether the roof is up or down. The alarm should work with the roof down and the way to test it is to put something on the seat and then reach in to try to grab it. There is a delay period before the movement sensors are enabled, so you need to wait until the LED drops to a steady flash after locking the car.

As mentioned above, the immobiliser is entirely independent of the alarm system and will function even if the car is only locked with the key (i.e. alarm not set). On the later alarm, the immobiliser can be used to disarm the alarm should the remote battery go flat - the immobiliser chip is read via an inductive loop and does not need a battery in the key - simply put the key in the ignition and turn to position II.

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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Fender2004
Joined: Fri 14 Aug, 2009 10:24
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  Z3 roadster 2.8
Location: Houghton-Le-Spring

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Fender2004 »

Thanks for the info Robert you never stop learning. :rtm:
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ARoosterinaRoadster
Joined: Thu 29 May, 2014 08:49
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  Z3 roadster 2.0
Location: Lancashire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by ARoosterinaRoadster »

Robert T wrote:The early alarm (separate fob type) has a pushable LED and the movement sensors are visible at the top of the windscreen pillars. Pushing the button disables the movement sensors.

The later alarm (buttons on the key) just has an LED light and the sensors are hidden in the footwells. Locking the car twice with the remote disables the movement and tilt sensors.

On neither alarm is there anything that detects whether the roof is up or down. The alarm should work with the roof down and the way to test it is to put something on the seat and then reach in to try to grab it. There is a delay period before the movement sensors are enabled, so you need to wait until the LED drops to a steady flash after locking the car.

As mentioned above, the immobiliser is entirely independent of the alarm system and will function even if the car is only locked with the key (i.e. alarm not set). On the later alarm, the immobiliser can be used to disarm the alarm should the remote battery go flat - the immobiliser chip is read via an inductive loop and does not need a battery in the key - simply put the key in the ignition and turn to position II.

Cheers R.
Hi Robert. Thank you. I have just been out again to the car and there are no LED's on the dashboard - albeit there is one on the front of the radio which flashers when the key is withdrawn and the car is either left unlocked or is locked with the key fob or the key.
I will check-out the hood down -alarm situation in the next day or so when I am away from our ultra quiet Cul-de-Sac of pensioners bungalows.

If it is anything like the siren on my Volvo V70 SE Geartronic there could be a rush on ambulances for the heart attacks that could follow !!!!!!!!!!!!!
Happiness is a well kept Z3 and preferably running with the hood down - weather permitting.
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Robert T
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  Z3 roadster 1.9
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Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Robert T »

The alarm LED on mine (later alarm) is between the seats on the rear switch panel. It looks like a switch blank with a slightly raised area in the center.

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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littlefeller
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Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by littlefeller »

how does the immobiliser actually work, I never use my brick fobs only the key, so if I lock with the key (no fob) then alarm not on but immobiliser is on. so is my key coded to the ecu? or does it use an immobiliser that doesn't communicate with the ecu? I have 3 ignition keys, 2 black and one grey along with I think is a small alarm key, all keys excluding alarm key work in the ignition. I also have 2 fobs (brick type) both have flat battery's and would need to be linked again I would presume, I quite often lean into my open top and pick things up off the passenger seat with no alarm going off but as im not using the fobs it now makes sense. the guy I brought the z from also didn't use the fobs (the batteries hadn't been changed for years), I was a little suspicious of his motives for not trying them. so if I play around with the alarm im not going to get stranded like my friend did, not only did he get stranded he also needed a re-wire to loop out both the alarm and the immobiliser, something that isn't that simple as there designed in such a way as to make this difficult if not impossible.
ARoosterinaRoadster
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  Z3 roadster 2.0
Location: Lancashire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by ARoosterinaRoadster »

Robert T wrote:The alarm LED on mine (later alarm) is between the seats on the rear switch panel. It looks like a switch blank with a slightly raised area in the center.

Cheers R.
Hi again Robert. Ah ha said the blind person. Yes,indeed there is one as you say. I had truly not seen that before as I am not really looking in that direction when in the car and until now have not had the need to look through the windscreen with the car locked and the alarm set.

I will investigate the hood-down scenario in the next day or so.
Happiness is a well kept Z3 and preferably running with the hood down - weather permitting.
Jonco
Joined: Sat 04 Jun, 2011 07:24
Posts: 402

  Z3 roadster 1.9
Location: Cheshire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Jonco »

little feller wrote:.............. I also have 2 fobs (brick type) both have flat battery's and would need to be linked again I would presume........
It is almost definite that you will have to re-programme fobs if batteries have been flat for a length of time. This may be of help https://zroadster.org/articles/3g-ews-r ... amming.24/

By just using the door keys you are only operating the central locking not any part of the alarm system. The extra small key you refer to is for turning the siren on and off in the engine compartment. HTH
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BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
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  Z3 roadster 1.9

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by BladeRunner919 »

littlefeller wrote: so is my key coded to the ecu?
Yes. There's a transponder in the key that is detected by an antenna around the ignition switch.
ARoosterinaRoadster
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  Z3 roadster 2.0
Location: Lancashire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by ARoosterinaRoadster »

Jonco wrote:
little feller wrote:.............. I also have 2 fobs (brick type) both have flat battery's and would need to be linked again I would presume........
It is almost definite that you will have to re-programme fobs if batteries have been flat for a length of time. This may be of help https://zroadster.org/articles/3g-ews-r ... amming.24/

By just using the door keys you are only operating the central locking not any part of the alarm system. The extra small key you refer to is for turning the siren on and off in the engine compartment. HTH

Hi Jonco. Well another little bit of essential detail learned - when I got my Z3 from the dealer that had taken it in as a PX against an SLK !!!!!!!! It had no little (Siren) key.

I guess that it is a trip to my local BMW dealer/parts department suitably equipped with a box of Paracetamol !!!!!!!!!!!!! and a stiff Whiskey (Irish) not Whisky (Scotch).
Happiness is a well kept Z3 and preferably running with the hood down - weather permitting.
Jonco
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  Z3 roadster 1.9
Location: Cheshire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Jonco »

ARoosterinaRoadster wrote:
Jonco wrote:
little feller wrote:.............. I also have 2 fobs (brick type) both have flat battery's and would need to be linked again I would presume........
Hi Jonco. Well another little bit of essential detail learned - when I got my Z3 from the dealer that had taken it in as a PX against an SLK !!!!!!!! It had no little (Siren)
Hi - the info I gave was for little feller's question on the house brick type. You appear to have a later version so the programming of keys is done differently by a sequence of holding down buttons on key fob - I confess I don't know much about that type but I'm sure somebody will come up with something - there is a `how to' article in the knowledge base.
ARoosterinaRoadster
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  Z3 roadster 2.0
Location: Lancashire

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by ARoosterinaRoadster »

Hi - the info I gave was for little feller's question on the house brick type. You appear to have a later version so the programming of keys is done differently by a sequence of holding down buttons on key fob - I confess I don't know much about that type but I'm sure somebody will come up with something - there is a `how to' article in the knowledge base.[/quote]


Hi again Jonco. Yes,I was vaguely aware of that and currently don't appear to have issues with my Key Fob albeit I - as yet - haven't heard my Siren (if one is fitted). Having looked under the bonnet and into the engine bay I cannot see one or anything that would suggest that there is a Siren somewhere else and linked with wires from a key position.
Happiness is a well kept Z3 and preferably running with the hood down - weather permitting.
bazza1966
Joined: Thu 21 Nov, 2013 10:09
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  Z3 roadster 2.8

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by bazza1966 »

Fender2004 wrote:On my car there are two sencers one at the top left and top right of the windscreen, so the alarm covers the cab area. The little Red led on your dash is a switch if you push it in it turns them off, and if the switch is in the out position they are active with the alarm.
Hi Fender thanks for info did not realize the LED was a button to turn the alarm sensors off :dunce: I have not been using the alarm with hood down as the flipping thing kept going off :head:
tried your little trick hey presto alarm works fine again TY :roll:
Bazza (East Dorset)
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Robert T
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Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Robert T »

The later alarm does not have a key for the siren, as it can be reset by putting the key in the ignition as I described above. The siren is located directly below the fusebox.

The immobiliser chip in the key is coded with a unique cyclic code and if I remember correctly there are just 8 possible "keys" for each car. The car can be programmed to disallow keys if they are lost (I've never done it before you ask). The immobiliser works in the same way for both alarm types, but the newer alarm has the added feature of disarming via the immobiliser. The immobiliser works by reading the code from the key and this allows the car to be started. After the car is turned off, the immobiliser will remain disarmed for a period of time (something around the 20-30 second mark). If you were to get a spare key cut, you would find that you can start the car with it if you have used an original key and then immediately try the new key, however if you were to try the new key on its own, it would not start the car, as the immobiliser would have armed itself. You can read about this in an old thread on here where someone had a spare key cut and then couldn't start the car with it. A cheapest complete replacement key (with chip, but without remote) is about £60 from the dealer and is known as a grey service key.

I believe that the later alarm is the more reliable of the two with the roof down.

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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littlefeller
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Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by littlefeller »

thanks folks, think that covers it. opened one of my fobs (the only one with a battery in) only to find that that too is flat :lol: will get another and try it out.
Fender2004
Joined: Fri 14 Aug, 2009 10:24
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  Z3 roadster 2.8
Location: Houghton-Le-Spring

Re: Z3 - alarmed whilst the hood is down !!!!!!!

Post by Fender2004 »

bazza1966 wrote:
Fender2004 wrote:On my car there are two sencers one at the top left and top right of the windscreen, so the alarm covers the cab area. The little Red led on your dash is a switch if you push it in it turns them off, and if the switch is in the out position they are active with the alarm.
Hi Fender thanks for info did not realize the LED was a button to turn the alarm sensors off :dunce: I have not been using the alarm with hood down as the flipping thing kept going off :head:
tried your little trick hey presto alarm works fine again TY :roll:
Glad you got it sorted :D
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