Headlight won't stay on low beam

Energy One
S

Speed_Yellow

New Member
I recently replaced the stock headlight with an LED unit. Tested everything successfully/carefully with just the ignition switch turned on (without the bike running (2005 Chopper)). However, when the bike is running, the headlight won't stay in low beam. It seems that during the first 5-10 minutes it's OK. Then it starts automatically switching to high beam. If I manually switch it back to low beam, it will stay there for less and less time the longer the bike is running. Maybe 5-10 seconds. Eventually, it immediately goes back to high beam after taking my thumb off the switch. Suggestions? I'm wondering if the LED draws so much less current than the original bulb, that the ECM is confused?
 
Iman

Iman

Well-Known Member
i have one installed with no problem. loose connection or frayed wire maybe?? - welcome from Coastal SC
 
JimNubs

JimNubs

Member
Speed_Yellow said:
I recently replaced the stock headlight with an LED unit. Tested everything successfully/carefully with just the ignition switch turned on (without the bike running (2005 Chopper)). However, when the bike is running, the headlight won't stay in low beam. It seems that during the first 5-10 minutes it's OK. Then it starts automatically switching to high beam. If I manually switch it back to low beam, it will stay there for less and less time the longer the bike is running. Maybe 5-10 seconds. Eventually, it immediately goes back to high beam after taking my thumb off the switch. Suggestions? I'm wondering if the LED draws so much less current than the original bulb, that the ECM is confused?
Click to expand...
What type of LED lamp are you using? H4 or an all in one lamp "in housing". Oh by the way, you may what to do an intro, or you will be hearing from a Mr. Franco.
 
BigDogBro1

BigDogBro1

Made in the USA
The EHC's have a failsafe circuit in them to turn on the HIGH beam filament when it senses the LOW beam has burnt out or does not draw a minimum amount of current or a voltage drop across the load. Not sure what type circuit the EHC uses.

If the aftermarket LED bulb doesn't emulate the standard H4 bulb close enough then you will get the effect you are currently seeing.

You could try installing a HIGH wattage resistor (ohms?????) in series or parallel (to add more load) to trick the EHC but, you could end up burning out the EHC headlight circuit and trashing the EHC.

You need to run a standard wattage H4 bulb with a ceramic hi-temp bulb socket or keep trying different LED bulbs until you find one that works well.

Welcome to the world of modifiying a Bigdog.
 
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