Td5 D2 electrics - Tungsten to LED (1)

Originally written Friday 13th March 2015 when I was considering the merits and pitfalls of LED versus tungsten/halogen bulbs...

Looked online into replacing the 12v bulbs with LED equivalents. Prices are keen on the Internet and if prepared to source direct from the Far-East, it is possible to get a full set of LED bulbs for the price of two Halogen headlamp upgrades, making it well worth the effort. 

I am currently interested in the LED technology, and while the market is still a bit of a minefield, with some careful study it should be possible to upgrade easily. I well remember the effect that changing the standard front sidelight bulbs to LEDs had when I first got Hx.

Research has uncovered a problem with respect to the directional beam pattern that a light reflector can generate using conventional Tungsten 'point' source and LED 'multi' point. It's not to do with the light output in terms of its luminance, but rather the specific space inside the reflector that the light originates from.

A serious miss-match can occur particularly with dipped and main beam headlamps that will cause the projected light beam to fall short of it's requirement and in effect become illegal for road use.

This probably explains why I can't easily find LED H7 bulbs, because they are not 'type approved' by the EU or whoever. I read that the only EU approved LED headlamp fittings are the ones designed by the manufacturer from scratch to use LED bulbs. This probably equates to why at night some oncoming vehicles are annoyingly dazzling with their driving lights even though they are set on 'dipped'.

So, perhaps the only upgrade option for Hx in terms of the driving lamps is the Xenon halogen route, the so-called 'Osram Nightbreaker' set. I can see the problem with projected beam design, but feel that for other light fitments that do not rely on beam projection, the LED route is still viable. 

Well the big question is do l buy some H7 LED just to see or stay with H7 halogen and convert all the others to LED..? Here are some illustrations of the differing light fitments in use on Hx...

HEADLAMPS   -  Both of the main and dipped headlamps use a 'H7' fitting bulb.

The fitted Halogen lamps measure 44mm from the base of the mount to the glass tip and the glass envelope is 11mm in diameter. These measurements are important as the physical size of the LED cluster can at times be too big for the physical space inside the light fitment. 

The Halogens are rated at 55w but this measurement really stands no comparison with LEDS as they run at a tenth of the power.  (And even less of the heat output). The only way to compare output is to use the measurement of 'Lumens', but Halogens (or any other traditional bulb type) are very rarely measured that way. Couple this with the fact that LEDS come in differing physical sizes denoted by '3528' or '5050'.

Crucially, the LED count does not define the Lumen count, however the more LEDS there are of the same rating then the brighter it will appear. Even more crucially, the measurement shown from the base plate to the centre of the filament (25mm in the above drawing) is vital to ensure that the design of the reflector and lens produce the required light beam projection.  Compare this with an equivalent LED bulb and the 'Achilles Heel' of the LED construction becomes apparent.  Filament bulbs are 'point' source while LED is a 'multi-point'  source.

Two photos showing H7 bulbs. The shear profusion of LEDs needed to produce a comparable output is noticeable. There are 120 individual LEDs mounted but importantly, it's easy to see here that the Halogen bulb produces it's output in a very concentrated 'point' source.

Hx has tungsten/halogen bulbs fitted. I believe that fitting these LEDs would not be road legal as the factory lens/reflector is not designed for them in terms of directing the light throw onto the road ahead. 

FRONT FOG/DRIVING LIGHT

Never had to change these on Hx. They use a H11 fitting which uses a base that has a 90 degree turn built into the fitting. Some LR sources give the fitting as H10 or even H7 but I think that confusion arises from earlier D2 applications. Hx has the 'facelift' circular driving lamps mounted in the front bumper.

The actual Halogen lamp is rated the same as the dipped headlight  (ie.12v 55w ) but the physical measurements are not the same...

Once again the measurement from the base to the filament  (31.5 mm ) ensures that the fitted reflector produces the correct beam. I feel however that the fitted reflector is 'plain' as is the lens so perhaps the beam projection is not that critical in this case. .?? 

Also, I have noted that one of the lenses has misted over with condensation no doubt encouraged by the high burn temp of the Halogen bulb.

LED H11 bulbs with 68 individual LEDs. I don't have any spare equivalent Halogen bulbs so I guess these will go in when required. The biggest hassle will be getting access to the fitted lamp positions.....

FRONT SIDELIGHT / SIDE REPEATER 

This is a cap-less '501' fitting also known as 'W5W' and rated at 5w for a Tungsten element.

The glass envelope extends to the base and the two bare electrode wires simply extend beyond the base of the envelope and are bent back on themselves in the socket to make the electrical contacts. These Tungsten bulbs generate a lot of heat when running. I recall them being fitted in the auto 300tdi and indeed how the blown sidelight on Hx had heat damaged the sidelight plastic mounting making replacement tricky. 

I am currently already running LEDs in the front sidelight positions. When I got Hx it arrived with a blown front o/s sidelight and I took the opportunity to replace it with an LED equivalent. I originally fitted LEDs with a kind of 'lens' casing to spread the light projection into the lens reflector. I was happy with their appearance and performance but I soon felt that there were more powerful LEDs available in a '501' fitting. 

Two types of '501' LED.  They are polarity sensitive so I marked the positive side with some red pencil which can be seen in the above photo. The one on the right has a single LED encapsulated in a plastic "lens' although all its light is projected forward. This was the first type fitted to HX and it lasted for several months before succumbing to the vibration of the then loose headlamp unit and it began to strobe when switched on..

By then I was in a position to replace them with the 10 LED units shown above and below. Unfortunately, the heat-damaged mounting for the o/s front sidelight meant that these lamps would not fit inside due to being physically thicker. It was only a few months ago that the issue with the mounting was resolved! 

These were fitted in August 2016 and are considerably brighter then the single LED bulbs used previously. 

FRONT/REAR INDICATOR / FOG-GAURD / HIGH-LEVEL / BRAKE/REVERSE. 

Conventional bayonet capped 'P21' fitting. Also designated  '1156' or 'BA15S' '7506'. All rated at 21w and measuring 48mm tall and 26mm at widest diameter of the glass bulb. There is a single filament inside the bulb. 

Conventional Tungsten and an equivalent LED. 

These are the same LED bulbs used in the reverse light position on Hx.

REAR SIDELIGHT/BRAKE LIGHT.

Bayonet capped designated 'BAY15D'  '7528'  '1157 ' and fitted with offset pins for the dual filaments. Rated at 5w for the sidelight and 21w for the brake filament. 

Interested in how the LED versions are able to change output from side to brake output. Is it simply current altering or physically turning on more of the LEDs?  Answer, it is current related. ..

A dual filament bulb and it's LED equivalent. Note the offset mounting pins.

80 LED diodes crammed onto the surface to presumably produce the equivalent 'Lumens' 

value of a Tungsten filament.

Above chart shows the various arrangements of the Bayonet fitting bulb case... BA = Bayonet.   15 = diameter of case  (minus pins).     S= Single.   D=Double filament.    Hx uses BA15S and BAY15D. 

INTERIOR / NUMBER PLATE BULBS

These are the conventional 'Festoon' type.

All are 12v and rated either 5 or 10 watt. That is a potential 40w draw (50 if the glove box is open) on the interior lights alone! The shear reduction in current draw afforded by swapping to LEDs is not to be underestimated. 

I have replaced all these tungsten festoon bulbs with equivalent LEDs running at a tenth of the current. I was even able to select the colour of the LEDS and have used red for the main interior but also fitted additional white LEDs in there as well as in the glove box and the rear number plate lights.

Festoon bulbs come in different sizes so a careful measurement of the casing length is required to ensure correct fitting.

For the record these are 36mm festoon bulbs. The LED equivalents are available in many colours and indeed differing 'patterns' of the arranged LEDs .

Td5 D2 electrics - Reverse Light Switch

Operation of the reversing lights is not part of the annual UK MOT test. (update: since May 2018 they are!) Any failure in their illumination is only really noticed when reversing in the dark and usually at a time when you could really benefit from their use.

For a long time, I have often felt that the main use of reversing lights on any vehicle is to alert other road users to the fact that the vehicle is reversing. I mean unless you fit a custom spotlight, the relative low power (usually 21w) of the reverse bulbs is not enough to 'light the way' as it were.

And so it was with myself and HX. It was only when my daily parking routine changed and I found myself regularly reverse parking at night onto a paved drive between gateposts and up to a brick wall that I noticed that the reverse lights would 'flicker' on and off seemingly of their own will!

The operation of the reversing lights is governed by a spring loaded manual plunger type switch mounted high up on the main gearbox casing close to the main gear lever. Here is a photo of it...

When reverse is selected with the gear lever, contact is made with the plunger by an internal extension on the lower gear lever and the plunger is physically pushed in causing the circuit to close and the bulbs to illuminate. 

When the gear lever deselects reverse, the switch plunger is released, the circuit is broken and the bulbs extinguish. All very automatic and maintenance free... until the problems start.

Diagnosis of any problem is easy enough. It's either faulty bulbs, wiring issues or freeplay wear in the ridiculously tucked away, awkward and inaccessible plunger switch.. Guess which one it was.?

The best way to check their operation is to place the gearbox into reverse and get an assistant to observe the operation of the rear reversing lights. It is possible to do this solo, the vehicle ignition needs to be 'on' but the engine must be stationary.

It was observed that both reverse lights would illuminate when the gear lever was moved to select 'reverse'. However, once selected, the inherent springing in the gear linkage and the reverse switch itself combined with any free-play will cause the reverse lights to extinguish as the pressure on the engaged reverse switch lessens.

Moving the gear lever from side to side when reverse is engaged caused the lights to flicker on and off and clearly points to wear in the reverse switch. If some sideways hand pressure was maintained on the gear stick the reverse lights would stay illuminated.

This turns out to be a common problem with the Td5 engine or rather more specifically, the R830 gearbox. A new reverse switch is cheap and easily available. However, it's removal and replacement could truly be a real pain in the neck...

REMOVAL / REPLACEMENT.

Research on the Internet threw up a little homemade video from some guy in New Zealand dealing specifically with the same problem and the removal of the gearbox mounted switch. Easily one of the best instructional vids I've ever seen. He had some kind of a body camera mounted on him as he crawled underneath. There was a real claustrophobic 'get out and get under' feel to it. He ended up having to modify a 19mm spanner in order for it to fit into the restrictive and very confined space between the fitted gearbox and the transmission tunnel.

The inherent ground clearance of the body makes the job possible with all the wheels on the ground, but getting 'eyes on the prize' once under there is not easy.

I had to use a magnetic LED work light and carefully place small mirrors ( I recall even taping one in a suitable position ) to allow a very narrow line of sight to the component. I must admit to enjoying that aspect of the job, and once it was all set up the actual removal and replacement of the component was a doddle!!

Having diagnosed the problem as freeplay and wear in the plunger switch, the solution is two-fold. Either remove and replace the reverse switch with a new one or simply remove the thick 2mm washer between the reverse switch body and the gearbox body...

Removing the washer is the cheap fix (providing of course that it hasn't already been removed) and has the effect of bringing the plunger closer to the gear lever so that when engaged the plunger travels further back into the switch body and holds the circuit closed by applying more force to the plunger.

Either solution requires removal of the fitted reverse switch and that is were the fun really starts...

Rave has a wonderful way of making this procedure look easy. ... To get anything near the above view with it's 'open' access means taking the gearbox out!

The reverse switch body is attached by 19mm nut 'flats' formed onto its body. There is a short electrical loom emerging from the end of the switch body that goes to a nearby connector. The easiest tool to use would be a 19mm open spanner but the location and accessibility of the fitted switch really does work against that assumption. In the end I went for the following. 

Also showing the 2mm thick washer.

The solution I arrived at was to purchase a 19mm 'Crowfoot' spanner and mount it to a suitable ratchet (May also use a small extension /adapter socket). 

Even then, due to the location and angle of the 19mm flats and the proximity of nearby gearbox casing ribs, I was only able to get less then a 1/4 turn. This was sufficient to 'break' the torque and I then used a 19mm ring spanner threaded over the switch body for a couple of turns till the switch could be undone by hand and removed from Hx along with the 2mm washer/spacer.

I cleaned up the switch and tested it's continuity with a multi-meter and as there was no problem, I elected to refit the switch minus the washer and everything worked fine from then on! (Sunday 14th June 2015).

The washer that I removed was a chunky 2mm thick. I got to thinking that it really had a 'spacer' type function as it was made of aluminium, or it could well have been plastic.

THE LIGHTBULBS.

Having sorted the switch out, I decided to upgrade the reverse bulbs to LEDS. .. 

Having sourced an LED alternative it's a simple matter of swapping them over..

I removed the light unit from the rear bumper, this gave me a chance to clean it up while swapping the bulbs over. I did one side at a time and I took the opportunity to compare the LED unit to the Tungsten.

The light output was a lot brighter and 'cleaner' then the fitted tungsten 21w bulb in the other reversing light position.

The other bulb shown above is the rear fog hi-viz. I thought about replacing this also with an LED equivalent..

LED 'bulbs' offer great advantages of power saving/output and longevity over equivalent Tungsten filament bulbs. However they do bring issues of 'light-throw' and 'beam projection' particularly when fitted into reflectors designed for 'point-source' filament bulbs. 

Td5 D2 Seats - Electric Seat Controls

ELECTRIC SEAT CONTROLS. 

Another recent E-bay find was a pair of electric seat controls c/w their wiring looms. Their purchase is a significant step for the project and attention now turns to sourcing the new seats...

There is a thriving second hand market in these components and they are all readily available online with some of the components still available 'new'. 

They still command good prices with the above set of loom, switch pack and mount plate/switches easily going for over £100 if bought separately. Just one of the switch packs is available new for around £80.

I managed to buy two complete looms for a bargain £35 aided by the timely arrival of a discount voucher from E-bay.

Accurately described as 'used' and in need of a clean there was also also an issue with a 'sticky but functioning' drivers lumbar control switch.

I took a gamble on being able to strip it down and clean it up to return it to a  fully functioning condition. 

First job was to investigate the 'sticky' lumbar control button shown on the right of the above photo. All of the control stalks are spring loaded to ensure that once released the switch 'button' returns to its neutral position.

A close-up of the affected switch button in position on its faceplate. Clearly visible is a dribbled residue below the button. When I first saw this I knew it was the reason why the switch was 'sticky'. I hoped it was some sort of spilled sugary liquid, but was also mindful that it could be residue from a burnt out electrical contact... When I removed the affected button, the spring return on the switch stalk worked fine pointing to an issue with the button itself.

This is a close up showing the gunged-up reverse of the affected lumbar button. The two 'sockets' locate onto the switch-pack stalks and the lower one here was causing the problem by overcoming the return-spring tension inside the switch pack..  The solution was a good clean and scrape out of the gunge and then the problem just went away...

Two photos of the front face of the switch-pack minus the mounting plate. The first shot shows the corresponding switch buttons.

All the fluff and debris was quickly cleaned away to reveal the springs in the stalk apertures. A drop of oil was applied to lubricate the mechanisms.

Worthy of note is the 'BMW' logo on the yellow label. Makes me wonder if this component is from the BMW parts bin.?  The '61.31..' number is a BMW parts number and a quick search online finds the same unit fitted throughout the BMW range from the early 90's onwards.

Another point to note... The hollow tubular switch stalks are missing their sprung (?) metal 'caps' ( which can be seen on photos of the new units, - see below.). They probably flew-off during the dismantling. 

They don't effect the function of the switches but they must be there for a reason. Perhaps its just to improve the 'feel' of the control, but I fancy that their real function may be to mount an LED bulb for internal illumination of the switch. I will have to research this and delve into the various BMW applications.

Well, having looked around the web, the idea of fitting panel lights is fading away.. I could  not find any direct reference to lights fitted onto the switch stalks on these BMW switch packs. But that's not to say it's impossible! The biggest hurdle will be in getting the button graphics to be translucent in order to allow the light to shine through.

Managed to download a photo of a BMW switch pack 'opened up'..

That just about satisfies my curiosity! A common problem is that the black plastic 'stalks' of the switch operating levers can break in two, or the small ball bearing rollers can become dislodged all leading to the above scenario.

This is a photo of the reverse of the mounted switch pack and it's corresponding loom connector. The loom connection is a clever sliding 'bayonet' type affair shown in the open position above and is a credit to its German design!

There are 12 pins on the back of the pack and all are numbered. The relevant Rave circuit diagram gives function paths for them all. Briefly, the 12v supply enters via Pin 5 for distribution via the 'closed' switch pins. There is a common earth Pin 6 connecting all the 'open' switch terminals. 

I think it would be possible to connect an LED across these two pins so that it would illuminate when power was present at Pin 5. Much the same as the window switches illuminate on ignition...

A close-up view of the switch-pack loom connector. The clever 'bayonet' slider is shown in its fitted position.

The pattern made by the sockets kind of reminds me of ancient writing or some sort of 'machine code'....

Curiosity gets the better of me and I took a look inside the casing, a neat hinged case affair. The red wire was causing some bulging of the case due to it being routed wrongly.

Each of the wiring looms is 'sided' and will only fit either the passenger or driver side. They are not interchangeable.

The grey multi-connects on each loom are physically different even though they each have 12 wires and perform the same functions. These female connectors are routed to the underneath of the seats where they connect to each individual frame mounted seat loom.

RH Seat  -  YML 100300 

LH Seat -  YML 100310 

Not shown on the above photos but also written on the labels is a test date..

RH   -  Fri  17-11-00 @ 09.49

LH  -  The  21-11-00 @ 08.55

That would make them older then the big fella itself..!!

MOUNTING THE SWITCH - PACK TO THE CONSOLE. 

The design of the switch-pack may well be German but the mounting method is a good old LR 'that'll do' affair. The switch pack is held onto the mounting plate by four thin flimsy plastic tabs that are just not up to the job and, in the case of the right-hand mounting plate, only one of the four now remain!..

On the centre right is the single remaining hooked switch-pack retaining tab.

Another view of the back of the mounting plate showing the same tab in the six o'clock position. The 12, 3 and 9 o'clock mounting tabs are missing.. As are a couple of 'locating' tabs at the top left.

What's particular galling, is the fact that the German designed switch pack still retains its four sturdy metal mounting 'springs' which remain unused for the LR install.

Two views of the unused metal mount spring plates. The last view shows another mount tab clinging on for its life in between those metal springs...!! 

Because of the lack of usable mounting tabs I will have to come up with some method of securing the switch-pack to the back of the mounting plate.

Knowing that the switch-pack is from the BMW parts bin, I decided to do some research online to see how it was mounted onto cars in the BMW range....

The two drilled holes in the top-plate either side of the hollow control stalk are used on BMW installs to locate counter-sunk mounting screws that secure the switch pack to its mounting plate. The visible heads of the screws are shielded from view by the switch button and it's something I would like to try.

A search is on for suitable screw heads before I commit to some drilling!

This image shows the mounted position of the electric seat switches on the centre console facing the Left-hand seat. The mounting plate simply pushes into a pre-cut hole and is retained by plastic lugs.

The above photo shows a new 'auto' centre console with the cut-out mounts for the electric seat controls on the side of the cubby box. Note also the leather trimmed lid on the cubby box.

Here is a photo of a 'manual' console complete with the seat control cut-out on the side of the cubby box.

The manual console in Hx lacks the pre-cut mount-holes for the seat controls and will either have to be replaced or have the holes fabricated. 

Second-hand prices for what is basically some shaped plastic put me off buying a centre console with the pre-cut cut-outs and I fancy having a go cutting out the holes in situ myself....    what could possibly go wrong...? 

MODIFYING THE CENTRE CONSOLE 

Started off by making a card template in the shape of the hole that needs to be cut into the side of the console....

Needed to get a nice tight fit around the contact points on the rear of the mount plate. After some modification, I arrived at the above and after tracing out the outline shape of the front face of the switch mount plate, I ended up with the paper template shown below...

This photo shows the Right-hand mount plate and drawn onto the paper template above it is the area to be cut-out of the console side. The paper template can be reversed to mark out the other side of the console. 

Also visible on the mount plate are two pencil dots that represent the holes to be drilled through the mount plate in order to better secure the switch-pack to the reverse of the mount plate.

Here is one of the templates taped in position. I was using this opportunity just to check it was feasible to do the work without removing the console...  (or the seat!).

The central window-switch panel can easily be removed for access, but the innards of the Cubby-box itself are pernemently attached to the centre console.

This does restrict the access behind the console panels, but it is still possible to look inside and get fingers in there to make sure everything is clear before the cutting commences.

I wanted to check that the insides of the centre-console side panels were not already 'pre-scored' with the outline for the fitted switch panel. I figured that as the console is a universal fitting on every Discovery, the moulding may have the locations for the switch panels, but not in this case. 

So it was back to final placement and the marking out for the cutting.. I thought of placing the switch panel higher up on the side of the Cubby-box, but realised that the clearance behind for the switch pack and the cubby box sides means that's not possible (?)

I modified the template a bit more by cutting out little triangular pointers that mark out the contact points for the switch plate. I then marked each point with a sharp pointed file and then joined the dots with a pencil to get the guide line for cutting..

Decided to use a cutting disc on the end of a flexible extension to a 'Dremmel' type tool. The disc easily sliced through the plastic panel, but I also made use of a craft knife to finish the cut.

tbc...