A poor ground could cause low beams to send power to the high beams, and vice versa.
LED headlights
- Thread starter Seventy8
- Start date
I don't know much about electronics, circuits and such. Is there something I should check beside the male plug and female receptor? I can reach under the headlights and kind of jiggle the wires but that doesn't cause it to happen. It seems like it happens sporadically when I switch from high beam to low beam.
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- Apr 22, 2011
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- Camarillo, Ca
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- 2006 ST1300A
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which one is going out?
The right side is a direct connection, the left side goes through relays.
You could just swap the two connectors to see if the problem stays with the bulb or follows the connector.....
Also check/clean your starter switch. It turns off the headlights when you start the bike. (the secret dim [to flash] button)
The right side is a direct connection, the left side goes through relays.
You could just swap the two connectors to see if the problem stays with the bulb or follows the connector.....
Also check/clean your starter switch. It turns off the headlights when you start the bike. (the secret dim [to flash] button)
Thanks! Right side (when seated on the bike) is the one with the problem. It doesn't really go out. What's happening is the high beam LED stays on or comes on when I switch from high beam to low beam. When it happens both the low and high LED's are on in the bulb. Testing in the garage today it seems to stay on a second or two after switching from high to low. Last night while riding, the high was flickering on and off with the low beams on. The bulbs turn off when I start the bike.
Sounds like a weird leakage current through the LED. Try putting the standard bulb in the hi indicator as an experiment.
- Joined
- Apr 22, 2011
- Messages
- 1,145
- Age
- 68
- Location
- Camarillo, Ca
- Bike
- 2006 ST1300A
- 2024 Miles
- 002552
Check/clean the dimmer switch.
Check that the green wires are ground (shorted to the frame of the bike)
Do you have any extra driving lights tied to the high beam circuit ?
then it could be a bad bulb..........
basic wire diagram for the lighting circuit attached.
Check that the green wires are ground (shorted to the frame of the bike)
Do you have any extra driving lights tied to the high beam circuit ?
then it could be a bad bulb..........
basic wire diagram for the lighting circuit attached.
Thanks for the diagram! Tomorrow I'll try swapping the connectors to see what happens then follow the suggestions given. I sure appreciate the help!
As I'm testing this, I have both mirror covers off with the turn signal wires disconnected. I waited until dark so I could ride it again and see what happens. I noticed that when I first start the bike with the switch in the normal low beam setting, the right side bulb lights both low and hi LEDS. After a few minutes, the high beam LED flickered a minute or so, then went out. As I ride, the right side will be OK on low beam a couple of minutes, then that side hi LED flickers for a short time while the low LED stays lighted. Then it goes out and is normal for a bit then flickers, and so on. No real pattern to it.
As I'm testing this, I have both mirror covers off with the turn signal wires disconnected. I waited until dark so I could ride it again and see what happens. I noticed that when I first start the bike with the switch in the normal low beam setting, the right side bulb lights both low and hi LEDS. After a few minutes, the high beam LED flickered a minute or so, then went out. As I ride, the right side will be OK on low beam a couple of minutes, then that side hi LED flickers for a short time while the low LED stays lighted. Then it goes out and is normal for a bit then flickers, and so on. No real pattern to it.
Bad ground wires up front seem to cause all kinds of headlight gremlins. My ST buddy had a problem with one or both high beams frequently staying on if he switched from low to high to low. His high beam indicator stayed on even if the high beams went out and the lows came back. If he left the high/low switch on low and turned off the ignition and restarted, the lowbeams came back from any previous condition and the high beam indicator when out.
He cured this by running a separate ground wire from the — terminal on the headlight to a frame ground. This probably means there's a dirty/corroded ground connection elsewhere. There are two or three ground points that seem to benefit from supplemental wiring.
Cleaning the High/Low and Start switches are definitely a good thing. He also got bit by the No Headlight / Dirty Start Switch bug. Cleaning that set him right.
He cured this by running a separate ground wire from the — terminal on the headlight to a frame ground. This probably means there's a dirty/corroded ground connection elsewhere. There are two or three ground points that seem to benefit from supplemental wiring.
Cleaning the High/Low and Start switches are definitely a good thing. He also got bit by the No Headlight / Dirty Start Switch bug. Cleaning that set him right.
I switched the connectors. I plugged the right side bulb into the left connector and vice versa. Still the same issue on the same bulb. The right side bulb lights up both the low and hi LEDS when the switch is on low beam. So, if the problem stays with the same right-side bulb with either the right or left plug, does that eliminate the grounding and switch issues as a cause? And there are no extra driving lights or anything on the circuit.
I'm no expert but it would seem to me that since the problem stays with the bulb rather than following the connections, that points at a bulb issue.
Assuming the bulbs are similar to the Eviteks, where there is a two-piece wiring lanyard (pigtail from the bulb, and a separate component consisting of a power supply with pigtails going to the bulb and to the bike connector) is it possible that there is a pinch or fault somewhere in that chain? Close scrutiny would be required, probably, and may not yield a result.
Out of idle curiosity and without knowing what it would indicate, if you disconnect the left bulb does the problem still occur? If so, would that prove anything, or rule anything out?
The Techmax is exactly like the one shown in post 130 except on the ST1300 it doesn't need the adapter ring shown in that photo. It's just the LED bulb with a 3-prong plug. It's a straight plug into the bike's connector socket. Not being very electrically inclined, I ordered another set of Techmax Mini H4 LEDs to see if it's a bad bulb. I also sent a message to Techmax through Amazon to see what they have to say. I'm going to take a look at the dimmer switch now to see what kind of shape that's in.
One more thing. I started this because one of my headlight bulbs burned out but I still have one good one. I plugged that back in and it works perfectly on both sides. Does that pretty much eliminate a dirty switch issue, grounding, etc. or with the different type of bulb (LED) could those things still be a cause?
That's called burying the lede. I'd say you found the problem and that you're probably not experiencing any other causes. But you won't know until you chase down every possible consideration and rule each out. Me I'd just call it a day and ride to give your fix a shakedown cruise.
>> That's called burying the lede. 
Well, tupperware side covers are off and I've ordered a new set of LEDs that should be here Friday. I think I'll wait and try a different bulb before I button it up. In the meantime, I'm watching youtube videos on electrical stuff and learning that I can use my multimeter for more than battery testing.
Well, tupperware side covers are off and I've ordered a new set of LEDs that should be here Friday. I think I'll wait and try a different bulb before I button it up. In the meantime, I'm watching youtube videos on electrical stuff and learning that I can use my multimeter for more than battery testing.
This seems weird. The Superbright position light LEDs arrived today. I installed those and while checking them out noticed the headlight LED I was having trouble with, now operated normally. No more high beam on/off issue while on low beam. At least for the 5 minutes I tested it.
Glad we could help. 
You obviously improved a poor connection.
You obviously improved a poor connection.
The gremlin is napping.
Job finally completed! I initially thought that when I installed the LED position lights the problem with the LED headlight went away. Wrong! When I checked the next morning, the same issue with the right side LED coming on with both high & low bean LED's lit in that bulb. My 2nd set of Techmax Mini H4 LED's arrived yesterday. I replaced the bulb that was acting up and the replacement worked fine. I went for a test ride last night and no problems. Double checked the lights today and all still good. The problem was a bad bulb in the original set.
Here's a caution though on cleaning the upper cowl. While I had the tupperware off I figured I'd wash up the 12 years of dust and dirt I had exposed including the back of the upper cowl with the headlights. I was careful to avoid electronic connections but used a light spray of water to flush off part of the back of the cowl while it was kind of tipped upside down. Some water drained through the inside of the headlight lens which I thought was sealed. Not so. I didn't get any on the reflectors but some washed down the inside of the plastic lens leaving spots. Nothing terrible but enough to tick me off.
I had a little trouble reinstalling the left side inner cowl but the thread on ST1300 Faring Installation gave me the help I needed.
I appreciate all the help and advice I got here. Thanks much!
Here's a caution though on cleaning the upper cowl. While I had the tupperware off I figured I'd wash up the 12 years of dust and dirt I had exposed including the back of the upper cowl with the headlights. I was careful to avoid electronic connections but used a light spray of water to flush off part of the back of the cowl while it was kind of tipped upside down. Some water drained through the inside of the headlight lens which I thought was sealed. Not so. I didn't get any on the reflectors but some washed down the inside of the plastic lens leaving spots. Nothing terrible but enough to tick me off.
I had a little trouble reinstalling the left side inner cowl but the thread on ST1300 Faring Installation gave me the help I needed.
I appreciate all the help and advice I got here. Thanks much!
Looks great! Well worth the effort once said and done.
Glad you got it sorted out. Will Techmax make good on the bad one?