I have no low beam... except when I slap....

IpswichST

IpswichST

Joined
Jan 5, 2013
Messages
190
Location
Ipswich MA
Bike
1994 ST1100 ABS
As Im sure in every state, you must have your bike inspected and get an inspection sticker. My bike was inspected in March... passed... everything must have worked. A few weeks ago I didnt have a low beam. Huh... so I slapped my headlight and sure enough it lit up. I know that when you slap a light and it goes on, that cant be good. Headlights are not something I have dealt with yet. So here are my questions:

1- Is there a high and a low beam.. separate bulbs? I mean I have high beam and for low beam.. nothing at all.
2- I have read that people use an H4 bulb... but what is all this talk about shims?
3- I have read about turning full right and sliding my hand up to pull a boot off and then moving a retaining clip... etc, etc. I have looked for posts with pictures but cant find any... Anyone know of a post with pics that show the whole procedure?

Im gonna jump over to ST-riders and see if there is anything there.. and Ill google this. If anyone has a good pic of what I need to grab... blindly.. that would be great!
 
Relay sticking maybe? Try and swap some relays and see if anything changes. I would also crack open the switch housing and spray some contact cleaner in there. That is pretty common but may not explain why tapping the light helps. Either way it is good preventative maint anyhow.

The H4 bulb is a design where high and low is in the same bulb.
The H4 use and shim is because the tabs on the OEM Honda bulbs are not H4 format but the plug is a H4 bulb. The only bulb that fits is one from Honda. Many people want a more powerful light so they go with standard H4 bulbs like siverstars. To make them fit you leave the top tab in place and cut off or bend the two side tabs so the bulb fits. The shim is used to help stabilize the bulb. Some also use a bit of a wire coat hanger.

You can go in like you mentioned and pull the boots and such to swap a bulb but if you get a low beam when you hit the headlight I don't know that it is a bulb. I would recommend that you change the bulbs by going in from the top if you have never done it before. I don't know of any photos because it is pretty tight and it would be tough to get a pic of it. As you mentioned you will be doing it blindly. Like I said I would go from the top. 3 screws to pull the windscreen and a couple more to pull the black bezel below the windscreen. Not too hard and might save some frustration. Once you have done it before then you can go in from the forks as it will be blind.

Oh and no vehicle inspections in MN...
 
Howe-
It might be as simple as the low-beam filament is broken, and when you slap it, it makes temporary contact and lights up....I've experienced that in halogen bulbs before. In any case, you'll have to pull the bulbs to see that the filaments are intact or if it is something else, perhaps a poor connection.

No inspections in Colorado. ;)
 
Oh another thing. Odds are even if it were a bulb issue both wouldn't act up like this at the same time. There are two bulbs and if they both come on when you tap the bike, I would really doubt it is a bulb issue.
 
Yep, two bulbs in an 1100 ... but I didn't see in the OP whether it was both bulbs or one bulb that is acting up.

Howe, each bulb has both a low and a high-beam filament.
 
My guess:
If you went from no lights to 2 lights with one 'smack' you don't have a headlight problem... you have an electrical issue...
 
Internet is down so just a quick response from my phone...

ill pull the bulbs and inspect them. I think that would be the first step.

BUt...

Do I understand correctly... 2 bulbs that both have high and low beams? If so then doesn't it sound a little coincidental that both low beams are out? And did I read that there is a relay? I would think then that the relay is acting up causing only my low beams to malfunction.

Ill dig into it tomorrow.
 
I would look at your switch... I have had a 'no lights' condition that was caused by a filthy hi/low switch.
Clean the switch with a plastic safe electrical cleaner (a can from the auto parts store) and some acid brushes to stir it around.
Then fill the area with dielectric grease to keep the area clean.

Good luck!
Mark
 
IpswichST said:
Internet is down so just a quick response from my phone...

ill pull the bulbs and inspect them. I think that would be the first step.

BUt...

Do I understand correctly... 2 bulbs that both have high and low beams? If so then doesn't it sound a little coincidental that both low beams are out? And did I read that there is a relay? I would think then that the relay is acting up causing only my low beams to malfunction.

Ill dig into it tomorrow.
Click to expand...

Yep, two bulbs. Like I said if both bulbs are cutting in and out by tapping on it I don't think it is a bulb issue. I would move some relays around. There is a high and low beam relay. Could just swap them. I have seen funny things from the switch pod as well on the bar but I don't think tapping the headlights would do anything. It is more like they are intermittent and if you go high you get high and go to low and get nothing or the other way.

Some people don't realize that both bulbs should be on with low and have a blown bulb on one side. In that case it could be a bulb issue and something else which is why I wanted to verify that when you get low that it is both bulbs. It helps lessen the likely hood that it is a bulb issue or not.
 
Soontobeone said:
Here is a link to show you how to change your headlight bulbs. https://www.st-owners.com/forums/showthread.php?64100-Headlamp-Bulb-Replacement-Pictures

it is not difficult, but it is a bit different than most people are used to doing.
Click to expand...

This is for a 1300 and he has an 1100. It is similar but not exactly the same. As far as clipping the tabs and the H4 bulb part it is the same. The retention mechanism is a little better in the 1300 so the shims or coat hanger mod isn't really needed like they are on the 1100.
 
The PO did do some technical mods before me so I'm hoping that maybe there might be shims in there already.

I think I'm going to swap the high/low relays and see if my problem flips. I don't think it's the switch... I'm slapping the plastic by the headlight not clicking the switch.
 
Do some logical troubleshooting ......

Were BOTH low beams out, or just ONE before the "smack" ? If BOTH, then you probably don't have a bulb problem. If just ONE, then it may be the bulb low beam filament. If BOTH, it may be the low beam relay.

Was the corresponding high beam also out , before the "smack" ? If so, you might have a ground issue at the connector for that particular bulb.

I doubt a "smack" at the headlight would have any effect on the operation of the low/high beam switch. Electrical problems can be fun troubleshooting, if you have an electrical diagram. Wthout one, sometimes it can be a bear. According to mine, the low/high beams don't use a separate ground. So if the main ground connection was bad, you would have a whole bunch of things not working properly. But a bad ground connection at the bulb connector would cause both the Low & High beam to not work or be really dim. Inspect the headlight connectors after you disconnect them from the bulb. I would check both, just for S&G's. Good Luck !!
 
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Here is how it was (is).... Turn bike on, no low beam at all... Neither bulb. Flick switch to high and there is light!

Im thinking relay. QUESTION... There are 2relays... A low and a high? Or one for each bulb? If one for low and one for high then I can switch them which would result in no high beam if in fact it's the relay.... Correct?

No low beam is my only electrical gremlin (currently).
 
IpswichST said:
Here is how it was (is).... Turn bike on, no low beam at all... Neither bulb. Flick switch to high and there is light!

Im thinking relay. QUESTION... There are 2relays... A low and a high? Or one for each bulb? If one for low and one for high then I can switch them which would result in no high beam if in fact it's the relay.... Correct?

No low beam is my only electrical gremlin (currently).
Click to expand...

Two Relays. One for High one for Low. Swap them and see what happens. If the failure follows then it is relay. Or if the issue seems to go away I would still say relay. It is possible that moving things around cleans contacts a bit or causes the sticky low relay to be fine for a while.

Oh and I sent you a PM...
 
Here is another post I found with a similar issue.

https://www.st-owners.com/forums/showthread.php?60501-No-ST1100-low-beam-high-beam-works

I found this image that does a great job of explaining the shim that you were asking about...

trimmingtabs.jpg

The reason you need the shim or the coat hanger modification is because with the bail clip in place the bulb will not be supported properly and it will move around. The 1300 supports the bulb a little differently so it isn't really needed. I went with the coat hanger on the 1100 as I didn't have shims handy when I had a bulb go out and I switched over to H4 bulbs. I will say that it was a PITA to get it in there and the shims would be way easier. MCL sells them. I was ordering some other stuff from MCL so I added a set of shims. I then converted the lights on my 1300 and tossed them in there but they really were not needed on that bike.

I was looking to see if I could find where the relays are on the bike. I don't remember off the top of my head as I have never messed with them. Do you have an owners manual I assume you don't have a Service Manual based on your questions. It will say in those where they are located. I could look in mine if you don't have it but I would need to run out to the shop.
 
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Logically, it seems like it's the low beam relay. Switching the low & high beam relays would tell you if it's a bad relay. But it's weird that a slap would clear the problem, if it's a bad relay. The relays are mounted in rubber and aren't mounted directly to the headlamp shell going by the pic in my manual, but they are mounted very close to the shell. My manual shows three relays in a row, behind the right side of the shell. The front is indicated as the low beam, the rear is the high beam, and the center is the bank angle sensor relay. But when I installed my HID spotlights, the front relay turned out to be the high beam relay. The relay with the RED connector IS the low beam relay. I think you will be able to figure this out - might be a connection problem. After you switch the relays, if both the low and high beams work OK, it may have been a bad connection at the low beam relay connector.

A wild card problem could be a low/high beam switch with too much low beam contact resistance. In the low beam position, the extra resistance might be high enough so the relay armature isn't pulled in from it's resting position. But a "slap" might cause the coil armature to move slightly, reducing the armature air gap and reluctance, and then allowing the available coil current to be able to pull-in the armature - no kidding. So before you swap relays, try liberally spraying the low/high beam switch with contact cleaner, just for the heck of it. That would save time messing around with the plastic.
Like I said in my previous email, sometimes these electrical problem can be fun !!
 
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Definitely clean your switch. I've ran into that problem in the past. Also clean your bulb connectors.
 
Here are 2 pics. As you can see there are 2 relays on one side and 3 on the other. The 2 relay side is the right side of the bike when you sit on it (and the 3 relay side is the left).

Where are the headlight relays? The pair on the right... or 2 of the 3 on the left? And, if on the left, which 2 are headlight relays?

Im gonna clean the switch (in case it is the switch.. and for preventative maintenance... cant hurt)

image(1).jpegphoto.JPG

Oh.. and how do you get to them? do I have to take the side of the fairing off? What a pain!
 
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