This is a general info/what we know type of information "dump" for the UK only supplied problematic 2-1 alarm system that the earlier cars came fitted with.
We currently have a 22 page (at time of writing this) thread for general discussion on the alarm issues/fixes and some of the info is confusing or just lost in a realm of mis-information.
What is it then?
It is a Cobra 4615 Thatcham Cat 2-1 Wireless Alarm system with the optional Cobra A5462 Microwave Sensor.
The system did not come fitted from the European factory. It was fitted by Vodaphone Automotive at the UK docks, obviously sub-contracted by Hyundai UK.
It sets from the car fob buttons. Using the physical key in the door lock does not set the alarm.
I’ll spare the detail of these models as Google can give you answers but suffice to say, they are cheap, they are nasty.
The main 4615 alarm provides exterior protection for the following:
Let’s start with the interior…….
Right then, my alarm goes off if it’s windy, hot, cold, a small animal trumps next to it. Must be the sensitivity right?
Not really, Microwave sensors do not pick up air flow or temps, just movement. Check the interior for insects etc. Closing the air vents will just stop physical objects entering the car. It is not atmospheric conditions setting the interior sensor off!
I fitted LED interior lights to my car, my streetlight is a newer LED one, my neighbour has a PIR security light that’s on/off all the time. Anything to do with interference and my alarm going off?
Nope, not likely.
Can the sensitivity be adjusted?
Yes, easily.
Sensor is up near the rear interior light:
Pop the lens cover out to gain access to the two screws holding the unit in.
Get a trim removal tool/use fingers to pull the light unit out and unplug - its quite tight.
Put your hand up in roof lining towards the front of car and there is the £40 delight that is the microwave sensor. It'll be velcro'd to the roof panel.
Adjust sensitivity using a small jewellers screwdriver (or similar)
Can the interior sensor just be unplugged?
Yes, easily. It makes no difference to the main alarm operation. It is just an optional add-on module.
Can the interior sensor just be turned off?
Yes but it has to be done every time you park up. It cannot be permanently disabled without drastic action (see above).
Why didn’t they just fit switchable Ultrasonic sensors in the interior instead like almost every other alarm system for the last 25 years (and the newer cars which now don’t have the sunglasses holder)?
More fitting time at the docks! (Extra cable running, removing bits of interior trim etc). Time = Money.
Onto the exterior……
Loads of cats are always around my car/people are always walking past etc. Are they setting it off?
Nope, the system doesn’t have shock protection or any proximity sensing. Someone could physically run up and down the car if they wanted and no alarm will be triggered.
Can I adjust anything to help minimise false alarms?
This is very simple, the alarm utilises all existing sensors/switches via Canbus connection input/outputs. Therefore, there isn’t much to check here. Moving on…..
But what about the siren……?
The siren unit is fitted in the engine bay with the following 2 main wire connections: Live and earth.
The Live goes straight to the battery for constant power and the earth is self-explanatory.
There is an RF Antenna with provides the wireless connection to the main unit (which also has an RF Antenna….obvs).
Here’s a bit of info regarding the RF Antennas from Cobra themselves:
“The RF antennas positioning (for both the main unit and the siren) is crucial for a proper system’s performance. They must not be cut, wrapped, connected to any other cables or to the vehicle body and they must be kept separate from the main wiring harness and as far as possible from metallic parts”.
RF Antennas? That means Bluetooth then, everyone keeps bashing on about the Bluetooth connection?
There is zero mention of Bluetooth in the Install Manual or User Manual for this alarm series or anywhere online. That’s odd as normally any Bluetooth enabled device must have Registered Bluetooth symbol/Reg Marks on their manuals. (Like the handbook for your car, it’s full of them). So are misinformed people (dealerships) just using the term “Bluetooth” to describe the RF Antennas?
Right then, my siren is wailing its tits off all night and Big Dave from down the road wants to cave my head in, I can just remove the power to the siren to shut it up, right?
Hmmmmm, careful with this. The siren unit has an internal battery back-up. Therefore, just removing the power connection to the car battery isn’t fool proof. It will still sound off…..probably.
Alright smart-arse, lets pull the connector out from the siren unit then?
Go for it! But be aware that battery back-up sirens normally have “Cable Cutting Protection” to signal a sabotage attempt. If you are going to try this then I recommend you fully remove the siren module as well and move it as far, far away from your car as you can before you try and arm the system again!
But if I do that, does the system still arm and not cause any issues? Or does the main unit and siren unit have to stay ‘paired’ to enable my car to lock/unlock/start properly?
Dunno, nobody has got that desperate yet?! Try it and do let us know.
Anything I can do to troubleshoot the siren unit?
Check the connections, give them a blast with contact cleaner, check and clean RF Antenna, check its position and make sure it’s pointing towards the dash and stable. There is talk that the siren units can be relocated as one of the many “fixes”.
(Edit: Details added to thread below)
Here’s another snippet of info from the Cobra Install manual regarding siren location:
“It can be installed in the engine bay or inside the vehicle far away from heating sources paying attention to keep the main connector oriented down”.
So the connection between siren and main alarm module is “wireless”?! Why didn’t they use a “wired” connection? Wired is better than wireless, always!
Same reason they didn’t bother fitting Ultrasonics in the interior. Longer fitting time on the docks = Money, money, money!
Someone has had their system converted from wireless to wired but they are in a lucky majority of one it seems!
Continued.......
We currently have a 22 page (at time of writing this) thread for general discussion on the alarm issues/fixes and some of the info is confusing or just lost in a realm of mis-information.
What is it then?
It is a Cobra 4615 Thatcham Cat 2-1 Wireless Alarm system with the optional Cobra A5462 Microwave Sensor.
The system did not come fitted from the European factory. It was fitted by Vodaphone Automotive at the UK docks, obviously sub-contracted by Hyundai UK.
It sets from the car fob buttons. Using the physical key in the door lock does not set the alarm.
I’ll spare the detail of these models as Google can give you answers but suffice to say, they are cheap, they are nasty.
The main 4615 alarm provides exterior protection for the following:
- Doors
- Bonnet
- Tailgate
- Microwave (Hyper Frequency) Sensors
- Interior Movement
Let’s start with the interior…….
Right then, my alarm goes off if it’s windy, hot, cold, a small animal trumps next to it. Must be the sensitivity right?
Not really, Microwave sensors do not pick up air flow or temps, just movement. Check the interior for insects etc. Closing the air vents will just stop physical objects entering the car. It is not atmospheric conditions setting the interior sensor off!
I fitted LED interior lights to my car, my streetlight is a newer LED one, my neighbour has a PIR security light that’s on/off all the time. Anything to do with interference and my alarm going off?
Nope, not likely.
Can the sensitivity be adjusted?
Yes, easily.
Sensor is up near the rear interior light:
Pop the lens cover out to gain access to the two screws holding the unit in.
Get a trim removal tool/use fingers to pull the light unit out and unplug - its quite tight.
Put your hand up in roof lining towards the front of car and there is the £40 delight that is the microwave sensor. It'll be velcro'd to the roof panel.
Adjust sensitivity using a small jewellers screwdriver (or similar)
Can the interior sensor just be unplugged?
Yes, easily. It makes no difference to the main alarm operation. It is just an optional add-on module.
Can the interior sensor just be turned off?
Yes but it has to be done every time you park up. It cannot be permanently disabled without drastic action (see above).
Why didn’t they just fit switchable Ultrasonic sensors in the interior instead like almost every other alarm system for the last 25 years (and the newer cars which now don’t have the sunglasses holder)?
More fitting time at the docks! (Extra cable running, removing bits of interior trim etc). Time = Money.
Onto the exterior……
Loads of cats are always around my car/people are always walking past etc. Are they setting it off?
Nope, the system doesn’t have shock protection or any proximity sensing. Someone could physically run up and down the car if they wanted and no alarm will be triggered.
Can I adjust anything to help minimise false alarms?
This is very simple, the alarm utilises all existing sensors/switches via Canbus connection input/outputs. Therefore, there isn’t much to check here. Moving on…..
But what about the siren……?
The siren unit is fitted in the engine bay with the following 2 main wire connections: Live and earth.
The Live goes straight to the battery for constant power and the earth is self-explanatory.
There is an RF Antenna with provides the wireless connection to the main unit (which also has an RF Antenna….obvs).
Here’s a bit of info regarding the RF Antennas from Cobra themselves:
“The RF antennas positioning (for both the main unit and the siren) is crucial for a proper system’s performance. They must not be cut, wrapped, connected to any other cables or to the vehicle body and they must be kept separate from the main wiring harness and as far as possible from metallic parts”.
RF Antennas? That means Bluetooth then, everyone keeps bashing on about the Bluetooth connection?
There is zero mention of Bluetooth in the Install Manual or User Manual for this alarm series or anywhere online. That’s odd as normally any Bluetooth enabled device must have Registered Bluetooth symbol/Reg Marks on their manuals. (Like the handbook for your car, it’s full of them). So are misinformed people (dealerships) just using the term “Bluetooth” to describe the RF Antennas?
Right then, my siren is wailing its tits off all night and Big Dave from down the road wants to cave my head in, I can just remove the power to the siren to shut it up, right?
Hmmmmm, careful with this. The siren unit has an internal battery back-up. Therefore, just removing the power connection to the car battery isn’t fool proof. It will still sound off…..probably.
Alright smart-arse, lets pull the connector out from the siren unit then?
Go for it! But be aware that battery back-up sirens normally have “Cable Cutting Protection” to signal a sabotage attempt. If you are going to try this then I recommend you fully remove the siren module as well and move it as far, far away from your car as you can before you try and arm the system again!
But if I do that, does the system still arm and not cause any issues? Or does the main unit and siren unit have to stay ‘paired’ to enable my car to lock/unlock/start properly?
Dunno, nobody has got that desperate yet?! Try it and do let us know.
Anything I can do to troubleshoot the siren unit?
Check the connections, give them a blast with contact cleaner, check and clean RF Antenna, check its position and make sure it’s pointing towards the dash and stable. There is talk that the siren units can be relocated as one of the many “fixes”.
(Edit: Details added to thread below)
Here’s another snippet of info from the Cobra Install manual regarding siren location:
“It can be installed in the engine bay or inside the vehicle far away from heating sources paying attention to keep the main connector oriented down”.
So the connection between siren and main alarm module is “wireless”?! Why didn’t they use a “wired” connection? Wired is better than wireless, always!
Same reason they didn’t bother fitting Ultrasonics in the interior. Longer fitting time on the docks = Money, money, money!
Someone has had their system converted from wireless to wired but they are in a lucky majority of one it seems!
Continued.......
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