Monday 18 December 2017

Td5 D2 electrics - facelift headlights

HX is a 2002 model D2 and as such is fitted with the so-called 'facelift' light units.


This was part of Land Rover's desire to tie-in design elements across their whole range of vehicles (apart from Defender). Other populist names for them are 'frog eyes' or 'four pots' but the term 'facelift' seems to be a universal moniker.

Much more subtle changes were made to the rear light clusters at the same time. The bumper mounted light units now contain the reverse and fog lamps, while the indicators were moved from the bumper up to the body mounted light fitting. Although the location and physicality of the rear light clusters did not change, the lens colours and the wiring looms certainly did.

It is possible to 'upgrade' early D2 light units to the later 'facelift' lights, but it is not as straightforward as it would perhaps appear to be. To install the facelift headlamps onto an early D2 and to do it properly requires quite a bit of work...  The wiring harness is completely different and the slam panel metal will need cutting back or even replacing, but that doesn't put peeps off doing it!


THEFT AND WANDERING AROUND LOST.

Creating a demand for the front 'facelift' lamps has fuelled a supply shortage. They are still readily available to buy new, but their cost is truly extortionate! Its sadly inevitable that the criminal element amongst us can see a market to exploit by robbing Pete to sell on to Paul.

Theft of the headlamp units on any Discovery is nothing new. Early D2 and D1 share the same headlamp mounting which was literally a push on/ pull off design. (A good example of the LR 'that'll do' mantra!) It's not hard to see how that leads to expectations that the 'facelift' units mount and dismount with the same ease.

Reading and speaking to D2 owners that have suffered this theft all echo their shock and anger at the speed and brazenness of the theft. The light units are literally ripped off the bodywork and the looms cut free. Almost always this is done without even opening the bonnet. To Hell with the Rave procedure! It's almost like someone knows how to go about doing this..

Anyone who's ever changed a light bulb on a facelift D2 knows the hastle. Firstly, you need to open the bonnet, remove the centre grill, and then undo and remove the three screw bolts holding the lamp unit to the body before moving the entire lamp unit forward to get access to the bulb covers. Doing all that surely shows how it's not possible to just 'pull-off' the light unit?? But then again I ain't thinking like a Perp. Just how is it possible to swiftly snatch the lamp units from the body without even opening the bonnet..??

Well, one thing I can state for sure, if you are ever offered or buy a facelift lamp unit that has ANY damage to the mounting brackets or locating lugs then it most certainly has been forcibly removed from it's mother Disco!

The body-coloured plastic finishing strip on the bottom of the lamp unit also plays a part in all of this skull-duggery. There is no way that this strip can just 'fall-off' or become cracked or damaged unless some Perp has had a go at removing it. It appears that removing the finishing strip will allow the Perp to get a good grip on the lamp body behind that strip.
So if you ever return to your 'facelift' Disco and find the finishing strip damaged or missing you can be sure that some Twat has had a go at nicking the lamp unit.


ATTACHMENT POINTS.

Not counting the loom, there are four attachment points holding the lamp unit to the bodywork. Three of them are screw bolts but only one of those attaches directly to the metal bodywork. The two bolts on the upper surface are only accessible with the bonnet open. They secure the lamp unit to the plastic adaptor plate that in turn is bolted to the slam panel..


The above photo shows one of the metal collets moulded into the top surface of the lamp unit that the upper screw bolts attach to..

The metal bracket on the inner side of the lamp unit provides a strong secure connection direct to the metal bodywork..


The fourth mounting point is really just a guide/ positioning pin that locates the lamp unit into a body mounted rubber grommet!

The 9-pin loom connector can be a pain to remove at the best of times! It's no surprise that Crims just chop through the wires for a speedy removal. (But, as I said earlier, the loom connector will be needed for a retrofit).

Looking at the 'cavity' revealed when the lamp unit is removed, it quickly becomes apparent that there is no physical connection between the bottom of the lamp unit and any part of the bumper or lower bodywork... The importance of the design of the plastic 'finishing' strip soon becomes obvious!


This is the RH headlight cavity showing the upper surface of the bumper and the vertical face of the bodywork mounting panel. The rubber grommet can be seen on the left and over by the black plastic grill can be seen the raised bolthole for the inner screw-bolt which is perhaps the strongest attachment point. (The enclosed cavity below the bumper is huge!)


The same area on the LH side, but the cavity below the bumper on this side is where the screen-wash bottle is mounted. The mounting bracket for the wash bottle fits into a shaped recess on the rear of the lamp unit but it is not attached to it..

Another view of the lower LH headlamp mountings. The rubber grommet can be seen on the right and the raised bolthole can be seen on the opposite side by the black grill.


ADDITIONAL SECURITY MEASURES

Lens guards and grills are available, mainly designed from the concept of off-roading, for which (to my eye) the light units are not. Mounting them requires the wing panel to be drilled for some self-tapping screws which have to be easily removed to allow for bulb-changing. Perhaps visually they provide a visual deterrent to a Perp, forcing them to seek an easier target?

I have also seen worried owners fitting some homemade metal straps and even cable-ties to help increase the physical security of the light-units. Cable-ties are great at holding things together and have been part of the 'emergency' kit for years, but all it takes is just one snip..

Insurance companies and law enforcement agencies often recommend 'security marking' of personal property to aid recovery after a theft or burglary. It's a mute point and is something I have never done before.

Marking personal property to appease the threat of theft somehow only makes that theft more inevitable and I feel it is surrendering to the creeping tide of anti-social shite..

So out came the Dremmel(!) and I set too with a handy engraving/carving bit. I cut the full registration of Hx onto each light unit in two separate locations. As I was doing this, I figured that these marks can just be grinded away for sure, but it sure would look ugly.

Thought about etching the reg onto the front lens; but decided against that. I intend to get a UV marker pen to write the reg where it will be visible when mounted to the vehicle..

ALARMING THE LIGHT FITTINGS.

While reading up about securing the 'facelift' headlamps, I found a reference to extending the fitted alarm system to 'cover' the lights.

This naturally got me interested and I set about investigating the possibilities.

The alarm system on a D2 includes an often overlooked bonnet switch that protects it from a forced entry. That's probably why Perps don't open the bonnet when stealing the lights (?).

There is a simple plunger type switch mounted by the air box that receives a voltage signal from the BCU when 'armed'. The closed bonnet holds the plunger contacts 'open' and if released, the contacts are 'closed' and the signal earthed. The BCU detects this and fires the alarm.

It is a simple task to extend the system to cover each light unit with its own 'plunger' type switch. The hardest part will be sourcing suitable switches and deciding the best place to mount them on the bodywork. My plan is to use the plastic trim as the trigger point figuring that it might just save the lamp unit providing the owner is within earshot..  

Searching around E-bay for suitable switches soon threw up these simple plastic plunger types that will do for the first attempt at alarming the light units.



CLEANING THE PLASTIC LENSES

Comparing the two light units together, it was readily apparent that the clear plastic cover of one of the units (the RH side) was a lot more 'cloudy' in appearance then the other one. I began to doubt if one unit was newer then the other one, or whether the effected unit was actually cloudy on the inside surface of the lens.


To remove the cloudy oxidation I used some 'Halfords' rubbing compound (toothpaste does the same job) applied with a clean damp rag and some elbow grease working a small area at a time and regularly cleaning it off to compare the progress.

Progress was swift and the reflective shine quickly returned although it still did not match the other unit. At this point I mounted a soft woolly polishing mop onto an electric drill and gently polished the worked area.This brought the shine back brilliantly and both units now match each other for sparkle!


Much improved! A quick easy fix.



DISMANTLING THE LIGHT UNIT.

As I mentioned above, I could not be certain that the cloudy appearance of the outer, clear plastic 'lens' was actually on the outside or the inside surface. I looked at removing the clear plastic covering from the lamp body initially just to give the inside surfaces a good clean.

Removal of the clear cover is unfortunately not so straightforward. There are plenty of locating clips all around the base of the clear cover, but the main method of joining the two is via a factory applied mastic/butyl strip that seals and locates the two elements together.

It is possible to undo this bond but it requires the application of heat to melt and soften the mastic to enable the two surfaces to be gently separated.

Careful use of a heat gun or 'baking' the entire unit in an oven for ten min (225°) will soften the sealant, and the process needs to be repeated to re-seal the lamp units. I decided to not attempt doing this.



UPGRADING THE LIGHT BULBS

The light units (UK spec) have four separate bulb holders in them. They are all standard Tungsten or Tungsten/Halogen single filament bulbs in three fitments. The sidelight is a '501', the indicator is a 'P21' and the main and dipped headlights are 'H7' fittings.

I have found the standard 'H7' dipped and main beam bulbs to be perfectly adequate for the job. The only upgrade I have considered is swapping them for the higher output Tungsten (Osram Nightbreaker) or replacing them with LED equivalents.

The LED market is constantly evolving. It seems that every six months or so, new improved versions come along and prices drop. The equivalent light outputs (measured in Lumen's) are comparable and LED is beginning to out-perform Tungsten based filaments.

Conventional Tungsten Halogen bulbs will emit about 1300 to 1500 Lumens including the so-called 'Nightbreaker' types. All Tungsten filament bulbs gradually loose efficiency during their lifetime of usage. 

Most LEDs operate at a minimum of 2000 Lumens. Many are capable of 3000 Lumens and beyond. LED output remains constant throughout it's working life.

I believe that outputs of 3000 Lumens and above are not considered 'road legal' so care in their selection needs to be exercised. 

Although these brighter LEDs consume more power and generate more heat then an 'ordinary' LED, they still offer major savings in power consumption over Tungsten.

The lower levels of heat generated by a working LED can lead to the front cover of the light unit frosting over and in winter conditions snow and ice can easily build up on the outer surface severely reducing the performance of the headlight.

It would appear that the writing is on the wall for Tungsten bulbs in general as the EU is trying to get them banned from sale due to their higher energy use. That probably explains the continuing development of LED and I am curious as to whether newly built vehicles have any Tungsten based bulbs at all?..