Thread: Combining high and low beams

Apart from the globes overheating and destroying the reflectors, if low beam is added to the high beam circuits then you may have no lights at all because of the overload protection built into the MOSFETS that are used to switch the lights, on unless a separate harness with relays has been fitted.

Originally Posted by LRT

I would be keen to know more about where bee utey would position the diode and what size he would use. Also bee utey, would you wire according to the attached dual wiring diagram?

Essentially the position of the diode is correct so long as you replace the lamp loads with relays to drive the lamps. Then a 1 amp diode will be enough although a 3 amp would be better if you use twin relays per side. Add a switch in line with the diode and you can select the feature for occasional use when required. Also don't use bulbs heavier than 60/55W or you will be sure to do damage to the lamp holders and reflectors. There are plenty of uprade globes available from most suppliers these days in this wattage rating.

Personally I wouldn't bother with this mod, I would just purchase a couple of those new LED driving lamps to come on with the high beam, and adjust them for best illumination in high beam mode.

2 BLACK LED Driving/Riding Lights 12V 20W 1700 lumen | eBay

Another simple option would be to install a set of white "fog" lamps...these can be on at all times, or switched with the high beam (like a set of driving lamps)to be on on high beam only as fill lights in liue of the low beam.
Personaly, I'd go with a good set of driving lamps (HID or HID upgraded) and you'll think you're driving in daylight.

i can be wrong-

i live in sweden and i have a d2 2004 and my father have a d2 2003
and i run both high and low filament at the same time on the standard H4 globe that fits the light housing? it is original her so i dont se anny problem whit it. SORRY about the bad english

Originally Posted by wopac5

Another simple option would be to install a set of white "fog" lamps...these can be on at all times, .

Not legally.

Originally Posted by greif

i can be wrong-

i live in sweden and i have a d2 2004 and my father have a d2 2003
and i run both high and low filament at the same time on the standard H4 globe that fits the light housing? it is original her so i dont se anny problem whit it. SORRY about the bad english

2003-04 models are twin separate hi-low beams running H7 single filament bulbs in each reflector.


Using Capitals, the difference between helping your Uncle Jack off a horse or helping your uncle jack off a horse...

Originally Posted by LRT

What is involved to combine the high and low beams on a pre-facelift Discovery II ? LRT

Very easy, I've done it on my pre-facelift DII

I've had my DII for a couple of years and I did the modification shortly after I got it.

I'm still using the same H4 Bulbs from when I did the modification, which are + 50% Brighter Halfords own brand (Halfords are a high-street car accessory shop in the UK), the bulbs haven't blown, the connectors haven't melted and neither have the reflectors.


As some of the posters on this thread have already noted, when you pull the switch all the way back to latch on main beam, the dipped beam extinguishes, throwing most of the light 'down the road' leaving a (relatively) dark area in the foreground

You can see the extent of this by 'flashing' - as this flashes the main beam, without extinguishing dipped beam.


I've now 'fixed' this annoyance, by releasing the Blue/Red (UR) wire's terminal from cavity 2 on the Lighting Switch Connector (C0041) and moving it to cavity 1 - dipped beam now stays on with main beam (as per some other markets)





The terminal can be released from the connector, by lifting the retaining tab, using a pin from the front of the connector, while pulling gently on the Blue/Red wire.

You can see the terminal retaining tabs in this picture -



(ignore the tick and cross against the terminals, this was to highlight (to a member on another forum) the difference between the correct Sumitomo terminal for this connector and the standard AMP type, which doesn't fit)


At some point in the near future, I'll be changing the H4 connectors for ceramic ones, with heavier gauge wiring and relays. Not because I'm worried about it burning out, but because it reduces the volt-drop at the connectors and makes the lights brighter.


Paul.

1989 Arles Blue 2.5TD 110 Hardtop
1999 Epsom Green Discovery II 4.0 V8i XS



.

Ya learn something every day.
I have never known it possible although I think my 130/90s would take a smidgeon of excess current.
Regards Philip A