High Beam dash light

motoddrob

motoddrob

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Location
S/W Australia
Changing the head light back to a normal H4 Halogen. The high beam dash light lights up on both hi and low beam.
If I unplug the globe from the connector and using a test light, low beam lights without dash light and hi beam with dash light, so working as it should.
So why does the dash light work on both beams with the bulb plugged in??
Should there be continuity between high and low terminals on the bulb?
 
motoddrob said:
Changing the head light back to a normal H4 Halogen. The high beam dash light lights up on both hi and low beam.
If I unplug the globe from the connector and using a test light, low beam lights without dash light and hi beam with dash light, so working as it should.
So why does the dash light work on both beams with the bulb plugged in??
Should there be continuity between high and low terminals on the bulb?
Click to expand...
They're both connected to a common ground terminal.

Are you getting seperate beams at the bulb or do they both light up in both switch settings? Changed anything at the 3 terminals at the bulb plug?

piet
 
Hi Piet,
I"ll remove the bulb and check if both beams are lighting up.
I expect continuity between ground and each beam but not between the 2 beams. Thinking it must be something to do with the bulb. I checked 3 new bulbs and al had continuity between beam terminals.
Test light on the terminal works as it should.
New bulb, old terminal block.

I've replaced the non operating HID lights with a H4 Halogen.

Sock, I'll run a ground directly to the battery to eliminate bad earth

Cheers
 
So today I removed the bulb from the head light to see what lights up.
Low beam, both filament light up with the dash light
Hi beam only the high beam lights up with dash light
Removing the bulb from the connector
Terminal, test light works on low beam only, and hi beam with dash light only.
On low beam there is no power on the hi beam and vice versa
So to me the wiring is correct to the terminal. Still not sure why there is continuity between hi and low spades on the bulb.
Changed the terminal block for another and same same.
Ran a ground wire directly from the battery to terminal block and no diff.
Sort of got me fucked!!
 
It has to be the bulb.
I connected it straight to the battery
Low beam and high beam both light up
Hi beam is just high beam
Adding a 2nd test light to the HB spade lights up in HB and lights up with low beam though the light is dimmer.
If anyone has a h4 halogen globe and meter at hand could you check connectivity between hi and low
and report your findings.
This is a new globe too
 
Is it a good thing or a bad thing to have both high and low beam filaments work at the same time when the high beam is activated, or independently, as far as illuminating the road or overheating the system? That's independent of having the warning on the dash light up when the high beam is on. That's definitely a good thing to be working. I remember lots of people saying their neutral light didnt work, and it didnt bother them; that would annoy me to the max.
 
Overloading of the system is a bad thing, plus the additional heat.
On the other hand, I’ve added a switch which runs both in series (what I think Rob’s doing by accident) which effectively runs both filaments at about 25% each, reducing power consumption and looking similar to a dipped headlight during the day.
 
Without a relay, running 60 + 55 watts through the light switch is a recipe for bad things. The LH ND switch actually operates both high and low midway between high and low - so there's a transition point in the switch. Never heard of a H4 that runs both H and L at the same time!

If it runs both when directly connected to the battery, Rob, it HAS to be an issue with the bulb.
 
How do you get a fault with a bulb but still keep it sealed, and dont they run nitrogen internally so the filament doest melt? Everyone has lost one filament, but having it magically connects both and still work.
 
I'm with Andy, looks very much like the ground has been misplaced... it is NOT the central terminal!

Otoh, it could be the bulb.:rolleyes: Internal shorts do happen now and then.

Running the headlights through a relay immediately sets a lot of watts free, actually allowing you to see something in the dark. Not uncommon to lose 2-3V at the switch when running the full current through it.

piet
 
Rob, naughty... must not overlook your hard won training, of past Stator RR problem solving acquired skill. Easy things first and observations. Insightful lads three had a clue, quickly.

Get in first, traditional/old blinker ( quaint term out here "Traficator" once upon a time ) indicator lamp works from the opposite non flashing side lamps return to battery negative, indicator lamp interrupted positive 12V from the active flashing side. Provided a proper battery negative is connected to the headlight shell arrangement, not through the steering head bearings.

Of tungsten filaments dropping onto the internal lamp lead in connections, known issue and usually causes fault currents with fuse clearing or breaker trip. Though mainly just fall away to the lower side of the bulb envelope. j
 
I was wondering when you'd pop up John. my most knowledgeable friend. So after Andy, Piet and Sock enlightened me to the earth issue and orientation of the pins yesterday I refitted the new headlight and I then manage to blow 7 fuses while chasing a short. It's very tight in there.
The new H/L, same part # as the one one I was using 15 years ago came with a massive big collar surrounding the globe that clashed with the fairing mounting bracket and Tacho cable/mechanism. An angle grinder with 1mm cutting disc soon disposed that. I had planned to use the old one with the stone chip and small hole with silicone plug until I dropped it on the concrete so 170 bucks later!!! Now the tach only fits on the piss as the globe retaining clip clashes on the tach cable. Nothing is ever straight forward. After re routing wires and adding shrink wrap to various connections the fuse no longer blows so success. I now have a working headlight. Those 2 small HID lights I fitted 15 years ago have been nothing but trouble from day 1. Now to blow some orange paint onto the replacement fairing and It'll be ready for a weeks road trip.
 

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As may be of use Rob, put an old headlight electrically across the fuse that is clearing, various methods apply, be careful as the lamp will be very hot, when the headlight is fully bright the short circuit is present. Investigate with the headlight glowing, when it dims the fault is located or found, if not cleared. 55-100W filament lamp required, not LED. HTH j.
 
That's a good tip John. ATM the problem seems to be solved. Not sure what was shorting but it was the park light that blew the fuse. Think it may have been the instrument lighting causing the problem. It would only happen when the headlight was bolted back into place. As mentioned there is not a lot of room there.
I'd like to go back to the original fairing if I can find a small LED projector lens unit 50mm in dia.
 
motoddrob said:
That's a good tip John. ATM the problem seems to be solved. Not sure what was shorting but it was the park light that blew the fuse. Think it may have been the instrument lighting causing the problem. It would only happen when the headlight was bolted back into place. As mentioned there is not a lot of room there.
I'd like to go back to the original fairing if I can find a small LED projector lens unit 50mm in dia.
Click to expand...

My daughters Kia Picanto has small lens like that. They are considered fog lights and are 55w, but if it’s form over function you’re after, you could use one as low and both as high.
 

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