AmLit

.020 Over
Joined
Feb 18, 2018
Messages
44
Location
Joplin, MO
Ride
‘05 Rocket III,
My low beams work fine but when I switch to High Beam, I get nothing from the headlights, both go dark. I’ve tested both lights and neither are burnt out and the indicator on the speedo does turn on.

Where would you look/test next? Thanks for your help!
 
Please add your model year to your info so it appears under your ride below your screen name - had to look through your old posts to see what you have.

If the indicator light comes on it's not the switch
The ground is common to low AND High beam - so not that either

Unlikely to be the headlight connectors, whether that be at the 4-ways where the headlight harnesses meet the main harness, or the headlights themselves.

Most likely problem*, honestly, is that the hi beam elements are burned out.
Have you actually tried a new bulb?
You say you 'tested' them - what did you do? Try in another vehicle or ????

*assuming wiring is stock - if it has an after-market bypass-relay kit then you would check the high beam relay of that kit.
 
Please add your model year to your info so it appears under your ride below your screen name - had to look through your old posts to see what you have.

If the indicator light comes on it's not the switch
The ground is common to low AND High beam - so not that either

Unlikely to be the headlight connectors, whether that be at the 4-ways where the headlight harnesses meet the main harness, or the headlights themselves.

Most likely problem*, honestly, is that the hi beam elements are burned out.
Have you actually tried a new bulb?
You say you 'tested' them - what did you do? Try in another vehicle or ????

*assuming wiring is stock - if it has an after-market bypass-relay kit then you would check the high beam relay of that kit.
To test the bulbs, I pulled them and ran two wires direct to a lawn mower battery checking the low side, then high. I was pretty disappointed when the high beam element turned on.

That’s all the further I got with it, I’ll have to pick up a new voltmeter and dig into it this weekend.
 
Please add your model year to your info so it appears under your ride below your screen name - had to look through your old posts to see what you have.

If the indicator light comes on it's not the switch
The ground is common to low AND High beam - so not that either

Unlikely to be the headlight connectors, whether that be at the 4-ways where the headlight harnesses meet the main harness, or the headlights themselves.

Most likely problem*, honestly, is that the hi beam elements are burned out.
Have you actually tried a new bulb?
You say you 'tested' them - what did you do? Try in another vehicle or ????

*assuming wiring is stock - if it has an after-market bypass-relay kit then you would check the high beam relay of that kit.
I’ve not considered the aftermarket by-pass. I’ll look for orange wires first thing.
 
@DEcosse put in my new LED lights out of curiosity. This was the result:
Low beam
6E56B8C1-CBE1-4C95-AB87-190EDDA67DD7.jpeg


High beam:
77E145B1-7CD4-43A1-AB1E-43093B58A5FC.jpeg


Some juice getting to the low beam element still, nothing to the high beam. Does that make sense at all?
 
.. Some juice getting to the low beam element still, nothing to the high beam. Does that make sense at all?
OK so it seems your earlier prognosis was correct in that the bulbs were probably OK too
The contradictory piece of data is that the Hi Beam Indicator lamp is coming on - that is fed after the Hi/Lo switch and after the Left Bar Switch to Main harness connector set which, as previously mentioned rules out the switch and the connector to it.
So something has to be compromised in the wiring from stock - again, the ground is common for both hi & low beams so its not that either.
That says that there is a 'break' on the high beam signal wire between where it leaves the right switch connector and the Connectors (two!) for the left and right lamps.
It really would make sense if there is a headlight relay kit, or some other wiring mod for the headlights.
The two intermediate connectors, the ones that feed the headlight sub-harnesses are under the tank, just behind the steering head on the right side

OEM_Headlight_Connectors.jpg


Check the sub-harnesses from there to the headlights themselves (going into the buckets) and also the wiring to those two connectors (which comes from the Left Bar Switch connector
Look for some DIY mod there .........
The wires on the main harness side of those connectors you are interest in, are the Blue/White on each connector (the Blue/Red is the Low Beam)
Those two Blue/White wires (one from each connector) are spliced, together with another Blue/White which feeds the Instrument connector, originating from the Left Bar Switch connector.
If you cannot see anything obvious at the exposed wiring close to the 4-way connectors then you may have to open up the harness to find the splice and look for possible compromise of the splice joint.
 
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for what it is worth i left my headlights on for hours and what happen is that it burned the ground connector left side (at the bulb) and when i checked the lights it had a weird apply it has been a long time but something like yours.
 
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