reading schematic help

[8ball]

been having a small problem with my headlight, it quit working. In diagnosing the problem I noticed the schematic shows either the symbol for a resistor at the headlight itself or they are showing to coil up some wire at the housing itself. when I bought the bike it had a headwinds headlight and I'm not sure if it was stock. I'm kind of leaning towards the hi low switch as my problem but I'm still interested in the symbol drawn in on the ground wire. Anybody run into this with there bike. 2004 Chopper, 117 motor

 

[Brew]

The schematic symbol on the headlight ground wire that you are referring to is "supposed" to be a "Choke Coil".
However, it DID NOT work for BDM on the headlight failure issues!
So if it's there fine, if it's NOT, it's fine too.

fyi: "If" you are having headlight failure issues, first check and see "IF" the headlight H4 plug is melted and/or deformed in shape.

- "IF" so, replace with a "High Temp." rated H4 headlight plug w/6 inches of 14 ga. "SOLID" wire pigtails connected by "individual" heat shrink-ed "Spade" terminals into your existing headlight terminals, via the headlight wiring harness, AFTER the "existing" insulated H4 housing is removed & discarded. (The increase in soild wire size & spade terminals acts as a "heat sink" to draw the excessive heat away from the NEW H4 plug & "terminals". This greatly reduces the risk of headlight failure!)

BDM Service Bulletin SB-1077
Make : BIGDOG Model : BOXER, BULLDOG, CHOPPER, DAYTEC CHOPPER, MASTIFF, PITBULL, RIDGEBACK, T CHOPPER
Year : 2004
Manufacturer : BIG DOG MOTORCYCLES, LLC
Service Bulletin Number : 1077 Date of Bulletin : JUN 16, 2006
NHTSA Item Number : 10020065
Component : EXTERIOR LIGHTING:HEADLIGHTS
Summary :
HEADLAMP CONNECTOR MAY MELT, MAKING BULB REPLACEMENT DIFFICULT. *TT

These "Headlight Remedy Kits" can be found online on ebay, sometimes, or contact DeadOneCustoms@Yahoo.com and he'll either have one he'll sell you, or he'll make you one up.

- But "IF" the headlight H4 plug is NOT melted, nor you've found any headlight wiring harness issues. It may be that the EHC Headlight Circuit has gone bad within the EHC controller. It's a VERY common issue within the '04 EHC controllers. (A little different circuitry within the '04's, than in the '05 & newer EHC controllers. The '04 design was more likely to "permanently" fail due to NO internal "individual circuit surge protection".)

I hope that this helps.
Good Luck!

 

[8ball]

got the heavier plug in the headlight housing so i figure the previous owner had changed this out before i bought it. Brew correct me if I'm wrong but this system works by powering the selection switch"hi, lo beam" which sends the signal to the ehc which in turn sends the power to the selected element in the bulb then to ground to the battery. In saying this is correct I should see power in the yellow or white wire if the selector switch is working right? By the way thanks for the help Brew. Not incompetent just not the best troubleshooter. 8ball

 

[Brew]

Yes, the "+12VDC" is sent to either the "White" wire (High Beam), or the "Yellow" wire (Low Beam) when the desired switch is selected by the operator.
However, there are a couple of automatic function that need to be taken into consideration, within this circuit design.

- The headlight will ALWAYS automatically "Default" to the "Low Beam" when powered up.

- Also, there is a SAFETY FEATURE that will automatically "switch beam selection" IF there is a fault detected on either beam circuit! It will automatically switch to the opposing beam.

-Not 100@ sure on the '04 EHC's, due to the lack of available info, but on the '05 & NEWER EHC's, "IF" both headlight fault indicator LED's are continuously switching on & off on the EHC. The EHC is most likely GOOD. But there is a FAULT somewhere in the headlight wiring harness between the headlight & the EHC. And it will most likely be the "Ground" wire (Black) due to it is common to both the high & low beam circuits.

I hope that this helps! : )

 

[8ball]

will try a outside ground ran to the battery and connect at the headlight and either rule it out or find my problem. Also I haven't seen any lights at the ehc for the hi or low beam. Thanks again for your time and your expertise, your the kind of guy that makes this forum great. Safe riding bro!

 

[standuprick]

Just bought mine and had a problem with the headlite. Follow the wires to where they plug into the harness. Check for power there. I did find my hot lead grounded on the tank. I found an extra unused connector. I believe it would be for a tach(which I dont have) so I switched wires. Problem was fixed. You can take the switch off and test the wires. Wiring can be tricky to diagnos a problem.

 

[8ball]

thanks standuprick will try that