Advertise on DISCO3.CO.UK
Forum · Gallery · Wiki · Shop · Sponsors
DISCO3.CO.UK > Technical (D4)

Trailer, how does it know?
Post Reply  Down to end
Page 1 of 1
Salty Spuds
 


Member Since: 05 Dec 2009
Location: The Peoples Republic of South Yorkshire
Posts: 86

England 2012 Discovery 4 3.0 TDV6 HSE Auto Unknown ColourDiscovery 4
Trailer, how does it know?

Does anyone know what mechanism the D4 uses to detect when a trailer is plugged in? Is it the bulb monitoring pulse sent to the indicators or is something else at work?
  
Post #62608923rd Mar 2010 7:41 pm
View user's profile Send private message View poster's gallery Reply with quote
Discobailey
 


Member Since: 13 Jul 2010
Location: Leeds west yorkshire
Posts: 43

United Kingdom 2010 Discovery 4 3.0 TDV6 GS Auto Nara BronzeDiscovery 4

I would say the D4 monitors/knows the power needed to supply the reversing lights on the Disco. When this is exceeded by adding further bulbs on a trailer, the black box knows a trailer is fitted and turns off the reversing bleepers!

Simple
Laughing Laughing
  
Post #68325217th Aug 2010 8:59 am
View user's profile Send private message View poster's gallery Reply with quote
mwestcrew
 


Member Since: 24 May 2005
Location: Warwickshire
Posts: 334

United Kingdom 2011 Discovery 4 3.0 TDV6 Landmark LE Auto Fuji WhiteDiscovery 4

Sorry but it's not connected to the reverse lights, a standard 7 pin connector doesn't have the reverse lights. On dual electrics the reverse light feed is in the grey connector.

Anyone here know the answer to the original question? I am interested to find out
 2011 D4 Landmark, Mini Cooper SD Clubman, Range Rover Vogue SE  
Post #68326017th Aug 2010 9:17 am
View user's profile Send private message View poster's gallery Send e-mail Reply with quote
disco4x4au
 


Member Since: 19 Jan 2006
Location: Perth
Posts: 409

Australia 

I believe it monitors the load on the indicator circuits. Hence if you have LED indicators, it doesn't know that the trailer is there.

Cheers,

Gordon
 ex - 2006 D3 TDV6 SE, silver, with lots of stuff - R.I.P.
ex - 2009 D3 TDV6 SE, silver, had lots of stuff too!
Now - 2010 RRS 3.0 TDV6, rimini red, 18" rims + Cooper LTZ, rear eLocker, Spider tuning box, GOE protection plates and rock sliders, GOE 3way shortened rods. 
 
Post #68354518th Aug 2010 12:05 am
View user's profile Send private message View poster's gallery Send e-mail Reply with quote
Salty Spuds
 


Member Since: 05 Dec 2009
Location: The Peoples Republic of South Yorkshire
Posts: 86

England 2012 Discovery 4 3.0 TDV6 HSE Auto Unknown ColourDiscovery 4

Yup, spot on. I had to fit some 21w ballast resistors across the LED indicators to get the toys to work. On the up side, the D4 doesn't have the "Strobing" indicator problem of the D3, I assume this is due the the LED rear clusters on the D4
  
Post #68573924th Aug 2010 7:34 pm
View user's profile Send private message View poster's gallery Reply with quote
GraemeS
 


Member Since: 17 Mar 2008
Location: NSW
Posts: 706

Australia 2010 Discovery 4 3.0 TDV6 SE Auto Nara BronzeDiscovery 4

I wonder if the D4 also considers the brake light load due to strange behaviour of mine. The trailer blinker indicator doesn't ever work but the parking sensors are disabled most times the trailer is used. I also discovered that the parking sensors don't start working again until the ignition is cycled. There's a possibility that the trailer blinker gobes are only 18W so I'll try some 21W although the only slightly greater current draw is unlikely to make any difference.
  
Post #68576824th Aug 2010 8:41 pm
View user's profile Send private message View poster's gallery Reply with quote
disco4x4au
 


Member Since: 19 Jan 2006
Location: Perth
Posts: 409

Australia 

Salty Spuds wrote:
Yup, spot on. I had to fit some 21w ballast resistors across the LED indicators to get the toys to work. On the up side, the D4 doesn't have the "Strobing" indicator problem of the D3, I assume this is due the the LED rear clusters on the D4


What resistance did you use - 10 Ohm?
 ex - 2006 D3 TDV6 SE, silver, with lots of stuff - R.I.P.
ex - 2009 D3 TDV6 SE, silver, had lots of stuff too!
Now - 2010 RRS 3.0 TDV6, rimini red, 18" rims + Cooper LTZ, rear eLocker, Spider tuning box, GOE protection plates and rock sliders, GOE 3way shortened rods. 
 
Post #68583025th Aug 2010 12:26 am
View user's profile Send private message View poster's gallery Send e-mail Reply with quote
Salty Spuds
 


Member Since: 05 Dec 2009
Location: The Peoples Republic of South Yorkshire
Posts: 86

England 2012 Discovery 4 3.0 TDV6 HSE Auto Unknown ColourDiscovery 4

If I recall, they are 6.8 Ohm wire wound with a heatsink case. I got them from RS for about £1.50 each.

PS just looked them up on RS http://uk.rs-online.com/web/search/searchB...6&y=11
  
Post #68587925th Aug 2010 9:09 am
View user's profile Send private message View poster's gallery Reply with quote
GraemeS
 


Member Since: 17 Mar 2008
Location: NSW
Posts: 706

Australia 2010 Discovery 4 3.0 TDV6 SE Auto Nara BronzeDiscovery 4

You need to be careful with the heat from the resistors lest you melt other wiring or set fire to the vehicle. You wouldn't hang onto a blinker globe for too long whilst its working yet the globe produces light as well as heat compared with the resistor dissipating all its energy as heat only. Stop at a congested corner for a little while with the blinker going and you could be in trouble. A 20W resistor acting as a blinker globe will get too hot to touch in only a few seconds.
  
Post #68595025th Aug 2010 12:18 pm
View user's profile Send private message View poster's gallery Reply with quote
Salty Spuds
 


Member Since: 05 Dec 2009
Location: The Peoples Republic of South Yorkshire
Posts: 86

England 2012 Discovery 4 3.0 TDV6 HSE Auto Unknown ColourDiscovery 4

It does get warm, I made up 2 aluminium heat sinks to mount them on inside the trailer board, just had 3 weeks towing the boat, so far so good.
  
Post #68596725th Aug 2010 1:28 pm
View user's profile Send private message View poster's gallery Reply with quote
Salty Spuds
 


Member Since: 05 Dec 2009
Location: The Peoples Republic of South Yorkshire
Posts: 86

England 2012 Discovery 4 3.0 TDV6 HSE Auto Unknown ColourDiscovery 4

GraemeS wrote:
I wonder if the D4 also considers the brake light load due to strange behaviour of mine. The trailer blinker indicator doesn't ever work but the parking sensors are disabled most times the trailer is used. I also discovered that the parking sensors don't start working again until the ignition is cycled. There's a possibility that the trailer blinker gobes are only 18W so I'll try some 21W although the only slightly greater current draw is unlikely to make any difference.


I don't think the brake lights make a difference. My trailer lamps are now fully LED including the brakes. The only mod I had to do to get everything to work was the aformentioned resistor across the indicators. Until I did that the indicators would work, but the car wouldn't recognise the trailer. Now I get the parking sensors disabled & the trailer light on the dash works. Have you had your towing electrics activated by the dealer? When I got mine in May, the dealer fitted & activated the electrics but the parking sensors wouldn't disable, there was a software update to fix this.
  
Post #68596825th Aug 2010 1:34 pm
View user's profile Send private message View poster's gallery Reply with quote
GraemeS
 


Member Since: 17 Mar 2008
Location: NSW
Posts: 706

Australia 2010 Discovery 4 3.0 TDV6 SE Auto Nara BronzeDiscovery 4

Use of proper heat sinks is the way to go.

The dealer checked my vehicle with their trailer test lead and all was well, so I can only assume my globes are slightly lower wattage.
  
Post #68611225th Aug 2010 8:27 pm
View user's profile Send private message View poster's gallery Post Reply
Display posts from the last:  
Post Reply Back to top
Page 1 of 1
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



DISCO3.CO.UK Copyright © 2004-2024 Futuranet Ltd & Martin Lewis
DISCO3.CO.UK RSS Feed - All Forums

DISCO3.CO.UK is independent and not affiliated to Land Rover.
Switch to Mobile Site