Headlight Issues
Hi all,
Forgive me if i break etiquette, I'm new. I'm in need of some help though.
I have an 01FXDL. Neither high nor low beams seem to work. Pulled the light, checked all over with multimeter. Light has continuity every which way. Two wires (green and red, as if that really mattered) show 12.8V alternatively, when the light switch is thrown, ground shows continuity, HIGH and low beam wire circuits show alternating continuity (appropriately, when the switch is thrown), and the voltage drops (as it should) when the starter is engaged. I tested the light bulb with alligator clips and it works. For fun a I stuck in a different 12V light - it also doesn't work.
I talked to two HD mechanics, and they concluded that I probably had a bad ground wire. Retested ground wire for continuity and it tests fine (as does the entire circuit, as indicated above).
And yet, no light. I'm at a loss. Any suggestions on how to get the light working, besides replacing this with an LED?
Forgive me if i break etiquette, I'm new. I'm in need of some help though.
I have an 01FXDL. Neither high nor low beams seem to work. Pulled the light, checked all over with multimeter. Light has continuity every which way. Two wires (green and red, as if that really mattered) show 12.8V alternatively, when the light switch is thrown, ground shows continuity, HIGH and low beam wire circuits show alternating continuity (appropriately, when the switch is thrown), and the voltage drops (as it should) when the starter is engaged. I tested the light bulb with alligator clips and it works. For fun a I stuck in a different 12V light - it also doesn't work.
I talked to two HD mechanics, and they concluded that I probably had a bad ground wire. Retested ground wire for continuity and it tests fine (as does the entire circuit, as indicated above).
And yet, no light. I'm at a loss. Any suggestions on how to get the light working, besides replacing this with an LED?
Electrical gremlins are tough to trouble shoot on the net.
Sounds like your checking it correctly, and have all the correct voltages. So you must be doing something wrong.
It's a hands on thing. Bring it over.
Sounds like your checking it correctly, and have all the correct voltages. So you must be doing something wrong.
It's a hands on thing. Bring it over.
It is very difficult to troubleshoot an electrical problem on a chat forum.
That said, I think you are describing a classic bad connection, probably on the supply side. You have checked for voltage but did you check with the lamp installed and turned on? You cannot check a circuit completely without loading it. You may well have a bad ground or loose or dirty connection somewhere that is not able to handle the current demand when the lamp is turned on. When this is going on, when you put your meter across the open circuit like you described, you can get good voltage readings but you should also read the voltage with the lamp installed and turned on...I bet you will find that you do not have good voltage then...bad ground circuit, relay contacts, fuse contacts, connector contacts, lamp connector, bad splice...something somewhere is loose or worn out and is not able to handle the current demand.
That said, I think you are describing a classic bad connection, probably on the supply side. You have checked for voltage but did you check with the lamp installed and turned on? You cannot check a circuit completely without loading it. You may well have a bad ground or loose or dirty connection somewhere that is not able to handle the current demand when the lamp is turned on. When this is going on, when you put your meter across the open circuit like you described, you can get good voltage readings but you should also read the voltage with the lamp installed and turned on...I bet you will find that you do not have good voltage then...bad ground circuit, relay contacts, fuse contacts, connector contacts, lamp connector, bad splice...something somewhere is loose or worn out and is not able to handle the current demand.
It is very difficult to troubleshoot an electrical problem on a chat forum.
That said, I think you are describing a classic bad connection, probably on the supply side. You have checked for voltage but did you check with the lamp installed and turned on? You cannot check a circuit completely without loading it. You may well have a bad ground or loose or dirty connection somewhere that is not able to handle the current demand when the lamp is turned on. When this is going on, when you put your meter across the open circuit like you described, you can get good voltage readings but you should also read the voltage with the lamp installed and turned on...I bet you will find that you do not have good voltage then...bad ground circuit, relay contacts, fuse contacts, connector contacts, lamp connector, bad splice...something somewhere is loose or worn out and is not able to handle the current demand.
That said, I think you are describing a classic bad connection, probably on the supply side. You have checked for voltage but did you check with the lamp installed and turned on? You cannot check a circuit completely without loading it. You may well have a bad ground or loose or dirty connection somewhere that is not able to handle the current demand when the lamp is turned on. When this is going on, when you put your meter across the open circuit like you described, you can get good voltage readings but you should also read the voltage with the lamp installed and turned on...I bet you will find that you do not have good voltage then...bad ground circuit, relay contacts, fuse contacts, connector contacts, lamp connector, bad splice...something somewhere is loose or worn out and is not able to handle the current demand.
Bingo skinman.
Just because your meter shows continuity, does not mean the circuit will carry current. It takes on strand of wire to show continuity.
Throw a jumper wire on that ground connection, with the light plugged in, and see if she comes on.
Just because your meter shows continuity, does not mean the circuit will carry current. It takes on strand of wire to show continuity.
Throw a jumper wire on that ground connection, with the light plugged in, and see if she comes on.
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