The Rover-Landers of BC

Pre-cursor: Using UK headlight speak so

dim-dip = 50% regular beams or whatever the equivalent is
dip beam = regular headlights
full beam = high beams

(have been reading mostly UK articles on the subject, hence why I am trying to keep things straight)

Have had a variety of things hampering my 90 lately. The most pressing of which is a headlight issue. I recently did a 12-hour drive through the snow, headlights working as normal. The next morning I flipped the headlights on only to find all I had was the infamous "dim-dip", barely enough to see by in the dark and only when nobody is oncoming. Both positions of the headlight switch resulted in dim-dip. No regular dip beam, and no full beam either (pushing the indicator switch away). Full beam flash still works (pull indicator switch towards you).

Have read I don't know how many articles related to the subject with suggestions even more numerous within them. Couldn't get a clear idea of what my problem might be.

Next morning while driving, headlight switch all the way forward, the dim-dips became dip beams. Tried the full beams and they too worked... momentarily. Went back to dim-dip and then moments later back to dip. Decided not to push things and turned headlight switch to dim-dip. After those brief moments of revival, no re-occurance of regular headlight operation.

The articles I read pointed towards three main issues:

Main headlight switch: The amperage going through the switch to run the un-relayed headlights heats up the plastic in the switch and the contacts push away from one another. Fix: Replace switch (subsequently fit relays to prevent it from happening three months down the road)

Indicator switch: Some people had the indicator switch go and simply replacing that brought back the full functioning full beams.

Behind dash relay ("pinky"): In some cases a relay behind the instruments fries itself and causes odd happenings with the lights. In many cases it is pink, however some are black (mine!). Some replace the relay and all is fixed, and others jump two terminals to kill off the dim-dip altogether.

So I ordered up a headlight switch and indicator stalk as a precaution. Replaced the headlight switch with new, no change in headlight function. Replaced the indicator stalk with new, no change in headlight function. Jumped the "pink" (mine is black, older style relay), and voila dip beams on both positions of the headlight switch. BUT, still no high beams.

Did some further wire tracing. Fuses are fine. Power through fuses when "flashing" full beams, but no power through fuses when indicator stalk in forward position (full beams on full time). I pulled up a wiring diagram:
Not seeing any mystery boxes, or weird connections, I am starting to wonder where I should go next. I have heard some mention of a "resistor" type thing on the inner wing that does the "dim-dip" thing, but haven't investigated there.

Anyone have a direction to point me in next?

It's currently -10C and snowing and I don't have a garage, so I am spending lots of time doing research on the subject on the computer and not that much time wandering through the wiring system outside...

PS. I have no way to check voltage yet, forgot it in the Lower Mainland. Am going to buy one tomorrow after work. Do have a test light.

As a follow up, took the test light out to the headlight switch and indicator switch.

The white plastic bit is the headlight switch and has the large blue and smaller red wire connecting. There is also a brown wire that connects to the hunk of solder between the two blue and red wires. At first position brown is hot (12V infeed). Second position (dim-dip) brown and red are hot. Third position (dip beams) brown, red, and blue are hot.

The indicator switch contacts for high beam can be seen at the top or right of the picture depending which way you see it. In the headlight switch third position (dip beams) I have power on both sides of the Full beam contact mechanism. However, when moving the indicator stalk forward to put Full Beams (High beams) on, it goes to ground. There is a contact on the bottom side that pulls away from the front contact as the visible contact makes contact. If I jump the contacts in the rest position I get Full beams (high beams). So it seems like I have a short somewhere... Any ideas?

Also as far as the indicator stalk wires go, no matter the position (two or three) of the headlight switch power is as follows:

Blue: Hot when Full beam contact in rest (middle) or flash position, nada when contact forward
Purple: Hot
Blue/White: Never hot
Blue/Red: Hot
Green (closest to purple): Hot (buzzes a relay when testing/hooked to oil pressure switch or something I read?)
Green (lower): Never hot
Little purple and black (hiding blue/red): Couldn't get the tester in there

Someone mentioned the Blue/White is the Full/High Beam wire...so should I be getting power through this when indicator forward?

Hi Dave,

Sorry, its pretty hard to help you online without getting in there and having a look....
One thing I can share is, all my past headlight / High beam issues have always ended up being relay related issues.

Have you done anything with the relays yet? If you have two of the same relays its worth just swapping them over to see if it makes a any difference. After the lights have been on for a while, feel the relays to see if any are getting really hot.

Good luck!
Andy

Relays?! You must have one o'them modern Land Rovers. Leather seats too huh? :lol:

Turns out you were on the right track though... Seems as though someone wired in a relay(Hella branded bright blue) for the high beams (or did Land Rover do this, as it looks pretty professional?). It was attached on the backside of the fuse panel at the gearstick, completely out of view. Only reason I found it was I was trying to trace wires through the five relays on the front. Gave it a cleaning and wiggle and all seems well. High beams do not work without it installed. It may have saved my indicator switch when on high beam as the bulbs I pulled out of the headlights were 100/90W !!! Almost double the stock 55/60W. I did notice that it appeared as though the high beam contact had at one time been fused together... Pretty black and roughly shaped.

Picked up some 55/60 as they were half the price of the expensive ones. Had to bypass the dim dip relay behind the gauges as well as it was shot too.

Built myself a new set of relays (one for high beams, one for low) and wired them straight off the battery, making use of one of the headlight connects to give the signals. All I can say is night is now day! Should have done it a long time ago.

I did try the 100/90W for 10 mins. They were EXTREME! And then they blew up rather slowly. Four weeks in subzero running at dim dip really sucked the life out of them.

Glad to hear you figured it out. My high beam relays are also in front of the gear stick below the fuse box so that sounds like a factory set up.
I noticed on cold days that the heater blows right onto the relays which doesn't help as they are already getting hot when in use. Maybe this helps to speed up the relay failure ....

Just as something to keep in mind on this subject, this is a nice option for a pre-built headlamp relay system: http://www.paddockspares.com/boomslang- ... -loom.html to take the load off of the switching.

Yeah pretty much the same as I built. Amazon.com also has all manner of "H4 relay harness". Don't ask me about quality though...