↓ Advertise on Defender2 ↓

Home > Td5 > Break inertia switch circuit to disable Defender
Post Reply  Down to end
Page 1 of 4 1234>
Print this entire topic · 
Spanner



Member Since: 16 Nov 2017
Location: Pembrokshire
Posts: 10

United Kingdom 2006 Defender 110 Td5 SW Zambezi Silver
Break inertia switch circuit to disable Defender
Hi all,

Recently bought a TD5 110 CSW and immeadiately got paranoid about security. I've bought a steering lock and pedal lock ('ardcase) but have been pondering whether it's reasonable to add a switch to the inertia cutout switch under the bonnet to disable the car. Have done a bit of searching but can't find whether this is safe/practical to do?

Thanks for any advice.
Post #674065 29th Dec 2017 11:55am
View user's profile Send private message View poster's gallery Reply with quote
roel



Member Since: 08 Aug 2009
Location: Lelystad
Posts: 2039

Netherlands 2003 Defender 90 Td5 PU Caledonian Blue
I am not an expert on this but this is a possibility but there are more.
The best protection is I think that the starter motor will work but the engine won't start. I think the thieves don't like noise. If the starter motor is't doing anything it takes time but it doesn't make noise so they have time for looking for the problem.

I am not sure what the inertia switch does. There are ways to prevent the engine starting even when the starter motor is turning over the motor. Roel

1984 90 2.5 na Diesel - RR V8 (1994-2001)
1997 Camel Trophy Discovery 300TDI (2001-2009)
2005 G4 Discovery III 4.4 V8 (2008-2018) It's gone but it still hurts.
2003 90 Td5 (2009-now)
Post #674276 29th Dec 2017 10:20pm
View user's profile Send private message View poster's gallery Reply with quote
Spanner



Member Since: 16 Nov 2017
Location: Pembrokshire
Posts: 10

United Kingdom 2006 Defender 110 Td5 SW Zambezi Silver
I agree regarding the noise from the Defender starter but I've yet to come across a way of doing this that matches my beginners knowledge of Defender wiring.

The inertia switch is designed to cut off the supply to pretty much everything in the event of an accident and is just a normally closed switch so another switch in series will break that circuit and cut off any way of starting the engine, even the supply to the ECU.

It's "silent" so not ideal but from what I've read on various forums if you leave a Defender anywhere, for any length of time, someone will nick it so I'm looking for something I'm capable of doing fairly soon.
Post #674285 29th Dec 2017 10:50pm
View user's profile Send private message View poster's gallery Reply with quote
bankz5152



Member Since: 02 Feb 2017
Location: South London/North Kent
Posts: 2166

2004 Defender 110 Td5 DCPU Epsom Green
Can always unplug the injector harness, itll crank over and over but never start unless its plugged back in.
Post #674293 29th Dec 2017 11:21pm
View user's profile Send private message View poster's gallery Reply with quote
grafty99



Member Since: 15 Aug 2012
Location: North Devon
Posts: 4785

United Kingdom 2002 Defender 90 Td5 HT Caledonian Blue
just unplug the inertia switch on the bulkhead Thumbs Up 2002 90 Td5 Station Wagon
1990 Vogue SE
Triumph Tiger Explorer 1200
Td5 90 Thread http://www.defender2.net/forum/topic50767.html
Tdi 110 Thread https://www.defender2.net/forum/topic69562.html
RRC Thread http://www.defender2.net/forum/topic54492.html
Instagram http://www.instagram.com/george_grafton
Post #674301 29th Dec 2017 11:52pm
View user's profile Send private message View poster's gallery Reply with quote
Spanner



Member Since: 16 Nov 2017
Location: Pembrokshire
Posts: 10

United Kingdom 2006 Defender 110 Td5 SW Zambezi Silver
To demonstrate my extensive knowledge, I think what you're referring to is under the bonnet.If so, I might get spotted unplugging it!
Post #674303 29th Dec 2017 11:54pm
View user's profile Send private message View poster's gallery Reply with quote
Spanner



Member Since: 16 Nov 2017
Location: Pembrokshire
Posts: 10

United Kingdom 2006 Defender 110 Td5 SW Zambezi Silver
Just found a video on YouTube and if the Defender is similar to the Discovery then my idea won't work as the hazards are activated when the inertia switch is open.

Looks like its back to the drawing board.
Post #674359 30th Dec 2017 10:41am
View user's profile Send private message View poster's gallery Reply with quote
Procta



Member Since: 03 Dec 2016
Location: Sunderland
Posts: 5166

United Kingdom 
roel wrote:
I am not an expert on this but this is a possibility but there are more.
The best protection is I think that the starter motor will work but the engine won't start. I think the thieves don't like noise. If the starter motor is't doing anything it takes time but it doesn't make noise so they have time for looking for the problem.

I am not sure what the inertia switch does. There are ways to prevent the engine starting even when the starter motor is turning over the motor.


what it does is kill the power to the fuel pump, if you have a crash. Also they known to fail too, so if the defender will not fire into life and the engine just spins over and over. This switch could have either tripped or the contacts failed in side the switch. I have had one trip out on me going over a speed bump Shocked

what the OP wants to do is make a plug and play harness with a switch on that bridges the fuel pump and the main loom.
Mount the switch somewhere hidden and you are a way. Thumbs Up Defender TD5 90 ---/--- Peugeot 306 HDI hatch back

Success is 90% Inspiration and 4 minutes Preparation # you can make it!
Post #674376 30th Dec 2017 11:39am
View user's profile Send private message View poster's gallery Reply with quote
Spanner



Member Since: 16 Nov 2017
Location: Pembrokshire
Posts: 10

United Kingdom 2006 Defender 110 Td5 SW Zambezi Silver
Could you explain what you mean by bridging fuel pump and main loom? I'd read somewhere that the td5 will run (roughly) without its fuel pump.
Post #674606 31st Dec 2017 9:20am
View user's profile Send private message View poster's gallery Reply with quote
TJH1985



Member Since: 22 Aug 2016
Location: Midlands
Posts: 238

United Kingdom 
My TD5 will start and do 35/40 without a working fuel pump, all feels normal except a lack of power. So wouldn’t stop it being pinched IMO.
Post #674611 31st Dec 2017 9:34am
View user's profile Send private message View poster's gallery Reply with quote
grafty99



Member Since: 15 Aug 2012
Location: North Devon
Posts: 4785

United Kingdom 2002 Defender 90 Td5 HT Caledonian Blue
Mine won't start and the hazards don't flash with it unplugged. I think the hazards flashing is a discovery thing Thumbs Up

Also, they don't know what you're doing under there, you can disconnect without it being obvious. Just leave the plug in place but disconnected Thumbs Up 2002 90 Td5 Station Wagon
1990 Vogue SE
Triumph Tiger Explorer 1200
Td5 90 Thread http://www.defender2.net/forum/topic50767.html
Tdi 110 Thread https://www.defender2.net/forum/topic69562.html
RRC Thread http://www.defender2.net/forum/topic54492.html
Instagram http://www.instagram.com/george_grafton
Post #674779 31st Dec 2017 6:41pm
View user's profile Send private message View poster's gallery Reply with quote
grafty99



Member Since: 15 Aug 2012
Location: North Devon
Posts: 4785

United Kingdom 2002 Defender 90 Td5 HT Caledonian Blue
Btw mine is on a hidden switch but until I wired it in I disconnected it manually if needed. Once you're in the habit it really don't take long Thumbs Up

Also applies to the 2.2 puma as well 2002 90 Td5 Station Wagon
1990 Vogue SE
Triumph Tiger Explorer 1200
Td5 90 Thread http://www.defender2.net/forum/topic50767.html
Tdi 110 Thread https://www.defender2.net/forum/topic69562.html
RRC Thread http://www.defender2.net/forum/topic54492.html
Instagram http://www.instagram.com/george_grafton
Post #674780 31st Dec 2017 6:44pm
View user's profile Send private message View poster's gallery Reply with quote
Spanner



Member Since: 16 Nov 2017
Location: Pembrokshire
Posts: 10

United Kingdom 2006 Defender 110 Td5 SW Zambezi Silver
I'm going to do this once the weather allows me to open the front door. A forum user (many thanks) has pm'd me an alternative way of switching which makes the whole thing seamless to use.
Post #674785 31st Dec 2017 7:11pm
View user's profile Send private message View poster's gallery Reply with quote
Procta



Member Since: 03 Dec 2016
Location: Sunderland
Posts: 5166

United Kingdom 
Spanner wrote:
Could you explain what you mean by bridging fuel pump and main loom? I'd read somewhere that the td5 will run (roughly) without its fuel pump.


basically make a plug in play harness with switch, that plugs to the fuel pump and to the loom ( the main loom) saves you cutting wires etc. So all you do is switch the power off.

If its running roughly with out the fuel pump, sounds to me that it might have a secondary one in the engine, that's powerful enough to still feed diesel through. Defender TD5 90 ---/--- Peugeot 306 HDI hatch back

Success is 90% Inspiration and 4 minutes Preparation # you can make it!
Post #674790 31st Dec 2017 7:35pm
View user's profile Send private message View poster's gallery Reply with quote
zsd-puma



Member Since: 09 Aug 2016
Location: Kent
Posts: 2720

United Kingdom 2010 Defender 110 Puma 2.4 USW Santorini Black
Quote:
If its running roughly with out the fuel pump, sounds to me that it might have a secondary one in the engine, that's powerful enough to still feed diesel through.


The injection pump will be able to suck a certain amount of fuel from the tank, but not enough to make the vehicle perform fully, so they fit an extra electric 'lift pump' in the tank to assist the injection pump.
Post #674821 31st Dec 2017 9:07pm
View user's profile Send private message View poster's gallery Reply with quote
Post Reply  Back to top
Page 1 of 4 1234>
All times are GMT

Jump to  
Previous Topic | Next Topic >
Posting Rules
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



Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
DEFENDER2.NET RSS Feed - All Forums