Headlamp Modifications

[mat_fenwick]

Well, I've just bought 6 relay sockets from VWP so I think my mind is already made up! With hindsight though it would have been a good idea to check how much was lost as heat through the resistor...
I usually use 55/100w bulbs, so I run no risk of dazzling when on dipped but have better illumination on main beam, which is what I use 90% of the time anyway at night. (One of the benefits of living in the sticks!)
I'm just reading the link now, thanks.

One more thing - it would be better IMO to run a seperate heavy duty earth rather than using a single headlamp connector to avoid voltage drop on the return path.

[electrokid]

I had another look at it yesterday before the lengthy task of wire brushing 4 wheels ready for shot blasting.

The current on dim-dip is about 2 amps per bulb so the resistors will probably be 3.3 ohms each - they'll be dissipating around 15 watts each so the loss on dim-dip is around 30 watts - not much of a saving for the occasional use it gets.

I got got diverted again thinking (wrongly) that the little plastic box close to the offside headlamp might be the thing that sorts out dim-dip - it turns out to be some fancy electronics that sits between the coolant low level switch and the dash display. I've drawn out the circuit of the electronics module - I think it's designed to flash the warning light - it's a very strange design - I'm still not sure if it's clever or stupid. One thing is for sure - designing something that is so closely controlled and uses 1% range resistors - and then hooking it up with connectors that are going to corrode is not sensible - and I've yet to prove if it's working or not.

It's not on any of the vehicle circuits I can find - GOSH THERE'S A SURPRISE

btw taking the earth connection to a solid chassis point should be fine.

[Mike E (uk)]

1% resistors are quite normal. (I use them for nearly everything.) The circuit would probably be fine with 5%.

Back on the light business, I was driving behind a VW golf today (I think) and the rear indicators were inside the circle of the brake lights!

I could hardly see them operating at all.

The design of effective car indicators was finished well over 30 years ago.
But a new car in 2010 has worse indicators than a 1970s car.

Fashion should not interfere with suitability for purpose.

Anyway, I challenge all BXs to a headlamp shoot out in Gaydon.

Mike

[KevR]

Fashion should not interfere with suitability for purpose.

Agreed – I'm both unfashionable AND unsuitable...

[rayfenwick]

The design of effective car indicators was finished well over 30 years ago.
But a new car in 2010 has worse indicators than a 1970s car.

Fashion should not interfere with suitability for purpose.

Hear hear!

Anyway, I challenge all BXs to a headlamp shoot out in Gaydon.

I don't want anyone shooting my headlamps out

[rayfenwick]

Agreed – I'm both unfashionable AND unsuitable...

Glad I'm not alone

[electrokid]

1% resistors are quite normal. (I use them for nearly everything.)

1% resistors should be the cheapest now because of higher demand / more volume / cost saving of quantity production - you'd possibly be hard pressed to find 5% resistors. But these are 1% E96 resistors from the E24 (5%) value range. There are other ranges of close value resistors - see -

http://www.logwell.com/tech/components/ ... alues.html

The resistors in the box are from the E96 range - 1% resistors from the 1% value range - six banded - with values such as 252K etc. These are off-the-shelf items but not from the Maplins of this world. I keep a stock of resistors from 0.082 ohm to 100 meg but amongst that stock are some 26.1K and some 422K - 1% range.

[electrokid]

Back on the light business, I was driving behind a VW golf today (I think) and the rear indicators were inside the circle of the brake lights!
I could hardly see them operating at all.

Yeah - that's dumb - and quite annoying too.

The design of effective car indicators was finished well over 30 years ago.
But a new car in 2010 has worse indicators than a 1970s car.
Fashion should not interfere with suitability for purpose.

Entirely agree - but it's happening everywhere - designers determined to learn from their own mistakes rather than learn from the past but then there's a bit of that in most of us but you'd think that the overall process which involves so many people would stamp on such stupidity at some stage.

My eyesight followed much the same degradation as my dad's so after he simply faded away (as old soldiers do ) in '99 I found his old reading specs very useful. They were 'half moon' or 'clergyman's' national health jobbies - look straight ahead over the top and the distance was in focus - roll your eyes down and look through the lens to read - perfect.

The day came when I knocked them off the edge of the workbench and one of the lenses broke. Things close at hand were a blur - the ability to probe one of the 106 pins of the 0.05" DSP chip a fond memory.

I went out a lunchtime to a couple of opticians who had never seen the half moon glasses before - but supplied me with something of similar strength to get by - slimline things - I had to bend my head down to look over the top for distance - and still bend my head down to look through the useless things.

Getting back to work the guy working next to me said "oh - you've got new glasses - they LOOK REALLY SMART.

I'll let you imagine my response let's say... it was 'informative' and 'forthright'

You'd think that with something so important as eyesight that 'fashion before function' would not apply - but it does.

[mat_fenwick]

Well, look what I've been busy with!



Two fuses as I didn't want the potential of a single fuse blowing and taking out all headlights! It all looks a little untidy but the plan is to put it all inside a case with just the two panel mount fuseholders on the outside. I have to test it first, and to do that I need to visit a scrapyard and scrounge 5 relays - watch this space for the next exciting instalment!

[electrokid]

ooo - looks good from here.

I didn't think about fuses but

Two fuses as I didn't want the potential of a single fuse blowing and taking out all headlights!

that's very sensible.

[mat_fenwick]

Well, many many relays arrived from Coventry today, plugged them all in for 'the big switch on' and..........not what I expected!
Dipped beam there is nothing, main beam there is dipped beam from one bulb and on dim dim I have 3 filaments glowing dimly. Back to the drawing board methinks. It's probably a mistake in my wiring - will triple check it at some point.

[electrokid]

Couldn't reliably connect to BXClub last night or this morning - at one stage I'd typed a reply and copied it to the scratchpad - then couldn't send it so I saved it instead. This morning I still couldn't get on and didn't know how long that would last so I posted it to you - with some IN4007s as well - you should get that tomorrow.

This was my saved reply...

Yes - check the wiring and check that you have the lastest drawing - the one with the diode with 'see later post' underneath it. There's only one copy of the drawing on page 3 of the topic - because I host my own pictures I simply modified the original drawing so if you made copies before I added the diode you'll have missed it but the drawing is still in the same place in the topic.

Diodes should be general purpose - IN400x series etc - check they're the right way round.

The circuit description is also on page 3 of the topic.

The circuit presumes that the following signals occur...

Ign only (all lights off)

Ign + side (dim dip operates)

Ign + side + dip (dip operates)

Ign + side + main (main operates)

From your description of what's happening it looks as though you don't have RL4 operating for starters - 'main' and 'dip' signals should go through diodes to RL4 and operate it - without RL4 operating the LH (on the drawing) bulb never gets its common connection grounded so the only filaments that will run on full brightness are on the RH (on the drawing) bulb.

On the + side - the original reason for the topic - I now have my LHD headlamps - many thanks to Richard

[mat_fenwick]

Thanks for your reply! I confess I haven't done any fault finding yet. Tonight I've been busy changing a steering swivel bush and putting extra batteries in the van in preparation for a trip to France. We'll have a 100Ah starter battery, and 290Ah of leisure batteries, which should keep us going for a while!

Yes, I have got issue 2 of the drawing so the extra diode is there - it may well be that one of the relays has stuck (in which case I blame it all on Vanny who sent them to me )

I was testing them on the bench, just with a set of jump leads so it's not the car at fault (although I am suddenly stuck by the thought that maybe there is a permanent live to the headlamps and 2 switched earths )
Will let you know what I find...

[electrokid]

thought that maybe there is a permanent live to the headlamps

I'm pretty sure I checked that and it's not the case - though that is a couple of weeks ago and I'm currently involved in laying concrete blocks - I'm sure that the boring task of cement rendering can lead to permanent brain damage

We'll have a 100Ah starter battery, and 290Ah of leisure batteries, which should keep us going for a while!

That's more over-the-top than my battery mod

I'll try to get the headlamp mod breadboarded soon - we will sort it out

[mat_fenwick]

Fault found and sorted...