Member Since: 20 Sep 2019
Location: West Sussex
Posts: 73
Alarm Going off randomly - Door Sensor
My 2016 D4 with a mere 14k miles seems to have an issue with the alarm system going off at random. Google points to checking hood (bonnet?) latch sensors and door sensors. They fail / get gunked up apparently? Seems crazy for a vehicle that's hardly got any miles. Any quick way to test these? Anyone with experience with this fault?
Unfortunately I am out of country for another week to look into this and the alarm has been going off multiple times in the night waking my poor pregnant wife and neighbours. We've resorted to having to leave the truck unlocked to keep the alarm disabled. Obviously not ideal.
Appreciate any advice!2016 D4 HSE Lux
Last edited by Surfrider on 18th Dec 2019 10:07 am. Edited 2 times in total
7th Dec 2019 4:58 am
BBDisco3
Member Since: 23 Nov 2008
Location: Cheshire
Posts: 3643
You could first try the single press of the key fob to lock the car as this excludes the interior motion detector. (Double press to include it)
If the problem still exists then the most common cause is the bonnet switch located below the offside catch. To isolate this you need to pull the plug off the switch and bridge the terminals in the plug (not on the switch) with a short piece of cable and tape it up temporarily. All accessible with having to remove anything.
7th Dec 2019 9:01 am
ronp
Member Since: 29 Nov 2006
Location: North Yorkshire
Posts: 15249
Have you checked the battery condition?
Especially if you leave the D4 unused over a period of time.
If do, you would get a message "battery low, start engine"
When the battery gets too low, this will set off the alarm....... always on the road less travelled 🚧
7th Dec 2019 11:28 am
pagoda
Member Since: 13 Aug 2009
Location: Not London Anymore (or the US for that matter)
Posts: 1928
Disconnect the bonnet wire and tuck it away. It's the first place to start I'd suggest. Happened to many. You can replace the catch if you want, but isolating it is a good place to start.PAGODA
8th Dec 2019 2:38 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4928
BBDisco3 wrote:
You could first try the single press of the key fob to lock the car as this excludes the interior motion detector. (Double press to include it)
If the problem still exists then the most common cause is the bonnet switch located below the offside catch. To isolate this you need to pull the plug off the switch and bridge the terminals in the plug (not on the switch) with a short piece of cable and tape it up temporarily. All accessible with having to remove anything.
+1 !yµ (idµ - eAµ) ψ=mψ
8th Dec 2019 2:41 am
Surfrider
Member Since: 20 Sep 2019
Location: West Sussex
Posts: 73
Thanks for the tips guys. I get back this week and can hopefully sort this out and get the truck locked again!2016 D4 HSE Lux
10th Dec 2019 2:20 am
pagoda
Member Since: 13 Aug 2009
Location: Not London Anymore (or the US for that matter)
Posts: 1928
You also have a truck?PAGODA
10th Dec 2019 2:34 am
Surfrider
Member Since: 20 Sep 2019
Location: West Sussex
Posts: 73
Well, Came home the other day to tackle this and the Disco has a dead battery. Hit the start button and it didn't even click to try and turn over. Just started throwing all kinds of wacky faults and alarms and flickering dash lights. Then electric power cycled itself to Battery Low, start engine. Didn't even register key fob to try and re-lock the vehicle afterwards.
I am assuming LR Approved Used warranties do not cover batteries?
Off to do some forum searching...2016 D4 HSE Lux
16th Dec 2019 6:43 am
Surfrider
Member Since: 20 Sep 2019
Location: West Sussex
Posts: 73
Well, new update..
Via forum searching, I found the CTEK MXS 10 to give a shot recharging and testing the battery. My multimeter showed it just under 10 volts when tested prior to charge. The CTEK did its thing overnight on the Recondition cycle and everything came up green and good the following day. Battery was 13.7v on the meter after. Disco started up just fine afterwards.
HOWEVER.. after driving around a bit, I had seen the message on the dash multiple times for the rear left door open and the overhead light popping on. This would cycle randomly a dozen or so times in a ~45 minute drive. My thoughts are this is what was causing the alarm to cycle and the overhead lights coming on drained the battery over the couple weeks I was away.
I started googling the door sensor diagnosis, but everything talks about the need to remove the door card. As the D4 is under Approved Used warranty, I think I will just make a trip to the local LR service centre.
Anyone else have experience with this?2016 D4 HSE Lux
18th Dec 2019 9:41 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4928
The switch is in the lock and this would trigger the alarm if faulty. The door card has to be removed so LR warranty should sort it. yµ (idµ - eAµ) ψ=mψ
18th Dec 2019 2:54 pm
Surfrider
Member Since: 20 Sep 2019
Location: West Sussex
Posts: 73
Just an update. Had this fixed same day by Land Rover Buckinghamshire under warranty. Invoice said they replaced latch and sensor. Problem hasn't come back in over a week now, however I only noticed that the keyless entry on that specific door doesn't work anymore. It locks when you press the button on the handle, but does not unlock when you grab / pull the handle. I assume they forgot to wire something back up. Off to LR it goes again...2016 D4 HSE Lux
4th Jan 2020 9:03 am
SteveNorman
Member Since: 14 Oct 2005
Location: Somerset
Posts: 1145
Quote:
Just an update. Had this fixed same day by Land Rover Buckinghamshire under warranty. Invoice said they replaced latch and sensor. Problem hasn't come back in over a week now, however I only noticed that the keyless entry on that specific door doesn't work anymore. It locks when you press the button on the handle, but does not unlock when you grab / pull the handle. I assume they forgot to wire something back up. Off to LR it goes again...
Or maybe the wrong latch for non keyless fitted?
regards
Steve
4th Jan 2020 2:48 pm
kamo1
Member Since: 09 May 2020
Location: Macclesfield
Posts: 62
IM having the exact same fault. replaced everything in the door still doesn't work, chased everything to BCU and no damage on that yet still showing that same fault meaning i can't lock the car without the alarm going off and draining the battery over night. Any ideas?
17th Feb 2021 5:29 pm
Balders of Cornwall
Member Since: 08 Jun 2020
Location: Saltash
Posts: 14
Alarm Nightmare
The alarm on my 2010 D4 xs is doing my nut in. I gave the bonnet latch a clean up, which seemed to help, but the problem came back a couple of weeks later.
Got a replacement bonnet sensor on order, but will try bridging the terminals with a wire, before the neighbours lynch me!
7th Aug 2021 10:37 am
desv8
Member Since: 01 May 2020
Location: CHELTENHAM
Posts: 133
I feel your pain and it would never go off in day light hours but wait until 3am.
As you say bridge the bonnet connections, this will confirm bonnet sensor fault.
Mine ended up being the ignition switch. When i unlocked and opened the door the warning chime for key in ignition would ring out. The car would lock fine and alarm would set, then at random think that the key was in the ignition and start alarming.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum