Head light issues

[donebysunday]

Bosch

Wouldn't it just be easier to replace the relay? Any 12 volt, 10 amp or better relay will work, I used a 'common as thieves' Bosch style relay 5 years ago to replace the stock one when it failed. Under ten bucks and under ten minutes...

Same type of relay I used for the FIAMM horns

Where did you get this Bosch relay ?
What do I/we ask for ?

Thank You ! Done };-)

[dondons1984]

Thank You Don and ALL trying to help me !!!!!

Checked the voltage at the batt. 12.65, engine running at 3K 14.50, Checked at the R/Y and 11.65.

Jumped the R/Y to the BL/BLACK and I have head light and dash lights, HI and LO beam.
So I could just leave these jumped and go but I'd like to resolve what the real culprit is !

(It always bugged me that the head light would come on and if the bike did not start the head light stayed on, so I'd switch off the key to kill the head light and try starting again continue this on/off ign. until it started.) Awe but this is for another post.

I'm thinking check the relay with the cover off to see if it's getting the power from the alt/gen. ?
OK the relay closes when the bike starts so it's getting the power from the alt/gen..
Funny thing as soon as the engine stops the relay opens back up again even with the key left on. At this point the engine will only run in the choke pos. as the fuel level is low in the carbs, just flip off the choke and engine stops.
Still the relay does not activate any lights. So I'm thinking bad relay ? ? ?

I think the previous owner had this issue with the bike I got. He installed his own holder for the fuse. Ill take a pic of it tomorrow and post it in photobucket for you to look at. I know that until my bike fully starts that my headlight doesnt come on but blinkers and all work.

[donebysunday]

Charging

I think the previous owner had this issue with the bike I got. He installed his own holder for the fuse. Ill take a pic of it tomorrow and post it in photobucket for you to look at. I know that until my bike fully starts that my headlight doesnt come on but blinkers and all work.

Even if the engine just pops tries to start the charging should engage this relay. The relay is supposed to close and send power to the headlight as soon as the alt/gen starts to charge.
Before this little problem I've got as soon as I hit the starter and the engine fired enough to turn itself over, even just a pop and the head light would come on. Blinkers and such are on a different circuit.

Hope to be of some help !

I know others will be the better at diagnosis.

[DGXSER]

I think the previous owner had this issue with the bike I got. He installed his own holder for the fuse. Ill take a pic of it tomorrow and post it in photobucket for you to look at. I know that until my bike fully starts that my headlight doesnt come on but blinkers and all work.

Not to total side track the thread, but....

It is not uncommon for folks who have issues with the stock fuses to pull the wires off the fuse box and put a replacement fuse in-line. Usually end up with no fuse box and all in-line fuses.

Under normal stock operation, all lights work when you turn the key to on, except the headlight. Because of the relay being discussed, the headlight only gets power when the alternator starts putting out power. It is a latching relay, meaning once the coil side gets power to connect the line side, it stays on till BOTH the coil and line side loose power. So, once the headlight is on, it stays on until you turn the key to the off position.

[donebysunday]

TC's fuse block

I think the previous owner had this issue with the bike I got. He installed his own holder for the fuse. Ill take a pic of it tomorrow and post it in photobucket for you to look at. I know that until my bike fully starts that my headlight doesnt come on but blinkers and all work.

One thing you will find is that just checking the fuses can break the old brittle fuse holders. These can be replaced for $2.50 each from your local dealer, this is what you should do if your looking for points at the cycle show (got yourself a show bike ?). When you do need fuses the ones at your local auto parts place will most likely be to long, you may be able to make them work but a little jiggle and they can slip down and loose contact.
Our forum administer TC sells replacement fuse blocks that use the auto stores blade type fuses. Other than the little work installing it and buying a hand full of fuses this is the way to go ! TC only charges $9.00 for this fuse block,,,,,, no brainer. As stated in another post you can spend a little more and buy spade fuses that light up when they blow, COOL HUH !

[Pizzaboy]

Thanks

for this Thread! I've been wondering why the headlight doesn't come on. I just picked up a 81 Venturer, Not running for 350.00 bucks. Put a battery in it, Now am disecting the problems. So after a New Starter soleniod and cleaning the starter button, switch housing and lubing the throttle cable while in there. I finally heard it run today, Although only on 2 cylinders, sometimes 3. So Now to the carbs and to check and see if all the Coils wires are getting juice. It has had Dyna Coils put in, and I saw some fellow on here had a good Idea of how to mount them-- think I'll be doing that as well, cause looks like the plug wires are hitting the tank. Anyway Great site, lots great info!

[MaximPhil]

for this Thread! I've been wondering why the headlight doesn't come on. I just picked up a 81 Venturer, Not running for 350.00 bucks. Put a battery in it, Now am disecting the problems. So after a New Starter soleniod and cleaning the starter button, switch housing and lubing the throttle cable while in there. I finally heard it run today, Although only on 2 cylinders, sometimes 3. So Now to the carbs and to check and see if all the Coils wires are getting juice. It has had Dyna Coils put in, and I saw some fellow on here had a good Idea of how to mount them-- think I'll be doing that as well, cause looks like the plug wires are hitting the tank. Anyway Great site, lots great info!

Hi Pizzaboy,
Welcome . Always good to hear of another 81H Venturer
Phil

[Pizzaboy]

Thanks Phil,

Yeah, I'll be hanging around for awhile. While I havent rode this bike yet, I think it'll be the bike for me. Inline 4 cyclinder performance, Luggage, Radio, Not too heavy, Lots of suspension travel, low maintence shaftdrive. how could I not love this bike?! I do have some issues to work through..Front brakes are not releasing, and now its not hitting on the middle two cylinders, but we'll get straight.

[ManagerMike]

Where did you get this Bosch relay ?
What do I/we ask for ?

Thank You ! Done };-)

Napa, any one of the following PNs: ar201, ar204, ar230 ar272, ar294, ar282, ar289, ar391, ar394, ar457, ar462 They all have the same Bosch connector form factor. From ~10.00 to ~$20.00.
You can put 1/4" female spade terminals on the existing wires, remove the terminals form the OE connector body and use those, or splice in the Napa connector body, PN ec23 ~$12.00.

[donebysunday]

Carbs filters

Napa, any one of the following PNs: ar201, ar204, ar230 ar272, ar294, ar282, ar289, ar391, ar394, ar457, ar462 They all have the same Bosch connector form factor. From ~10.00 to ~$20.00.
You can put 1/4" female spade terminals on the existing wires, remove the terminals form the OE connector body and use those, or splice in the Napa connector body, PN ec23 ~$12.00.

Thank You ManagerMike !
Love that bike, what a beautiful blue flake !
Your also very handy with making your own custom parts.

Now about those down tubes on the carbs ? ? ? Please tell me about these !

Thanks Again ! Done };~)

[ManagerMike]

Thank You ManagerMike !
Love that bike, what a beautiful blue flake !
Your also very handy with making your own custom parts.

Now about those down tubes on the carbs ? ? ? Please tell me about these !

Thanks Again ! Done };~)

Thanx for the flowers...

As for the carbs, plumbing parts at the local hardware and some "chrome" paint.

Look a bit closer and you'll see.

[donebysunday]

There are a couple items in that circuit. One is the relay that only lets the light come on when the charging system is putting out voltage. The other is the RLU which is a monitoring unit to detect if your low beam goes out and automatically switch to the high beam and light the indicator.

My best guess is your high low beam switch needs cleaning and or has a loose wire in there. However, it could also be the RLU is acting up. It can be bypassed. I think there is a tech tip on how, you jump two wires together, the blue black and the blue yellow.

Went to White Water again tonight. great ride out 40 mi., 1/2 mi. out of WW on the return trip the the RLU kicks in and all I've got is low beam. Flick the hi/lo a couple times and all I have is the low with the warning light on and near nothing for lights when switched. OK I'll ride on low as the high is gone
when there are no cars I try switching from low to high/ no high beam. OK hope the low works for the next 27 mi. to get home in the dark ! Flick the a few times more switch and suddenly the high comes on and the warning light goes out. All is fine to home. This is already jumped from the R/Y to the blue/black on the relay plug.

At a loss, got to be the RLU, no ?

[ManagerMike]

RLU or associated wiring, I eliminated the RLU on mine when I added a headlamp modulator. I still have it if you want it.

[3Phase]

Done,

As Mike said, check the wiring before you bin the RLU.

The High/Low switch itself could be dirty or have a broken/cracked solder connection. Make absolutely sure both filaments in the headlight bulb itself are good and its socket is clean and tight. Don't get mad at the RLU if there's an intermittent filament in the bulb or its socket is loose/dirty.

Another trouble spot is the Yellow or Green headlight High/Low wires in the switch connector on the left side of the frame under the tank. Make sure the connections are clean and tight. When the Yellow or Green wire connection gets corroded it'll start to burn and the RLU will treat it as a headlight filament failure, kick over to the other filament and light the warning light.

Turning the handlebars or just riding and moving the bike can flex the wires enough to temporarily break through the corrosion in the connector and the headlight will work normally until it happens again. Eventually you'll be able to see where the connector has been slow cooked and it'll be really easy to see the problem but harder to fix.

[donebysunday]

Rlu

Done,

As Mike said, check the wiring before you bin the RLU.

The High/Low switch itself could be dirty or have a broken/cracked solder connection. Make absolutely sure both filaments in the headlight bulb itself are good and its socket is clean and tight. Don't get mad at the RLU if there's an intermittent filament in the bulb or its socket is loose/dirty.

Another trouble spot is the Yellow or Green headlight High/Low wires in the switch connector on the left side of the frame under the tank. Make sure the connections are clean and tight. When the Yellow or Green wire connection gets corroded it'll start to burn and the RLU will treat it as a headlight filament failure, kick over to the other filament and light the warning light.

Turning the handlebars or just riding and moving the bike can flex the wires enough to temporarily break through the corrosion in the connector and the headlight will work normally until it happens again. Eventually you'll be able to see where the connector has been slow cooked and it'll be really easy to see the problem but harder to fix.

Thanks Scott and All !
I will go through all the wiring connections again. Might have missed something on my second or third, last going over ? Dielectric grease again and check tightness.

Done };~)