EHC replacement
- Thread starter Axel
- Start date
Axel
Active Member
Hi Fourbar,
My BD dealer don´t know about a ver. 2 schematic. It might be a different software but basically the same schematic.
Eric, your idea with a not working tester was right
The tester does not work with the Low Fuel LED. We just checked the Low Fuel led in combination with my EHC58E at a bike. A 180 Ohm / 1 Watt resistor will help to switch off the led if the tank is full. This might work for the other harness replacement solutions what are on the market. I already added it in my EHC in order that there is no additional resistor required. I attach the EFI schematic with a handmade drawing. The resistor is hanging between B32 and B40 and you might can put it in the B-connector or somewhere beside of the tach board.
We tested several resistances and the led was almost off with a 180 Ohm value. When you increase the resistor then the led will start to glow brighter. A value below 180 Ohm will result that the led will not glow. However a lower resistor value will increase the current through the temp sensor what will might result in a temperatur increase of the sensor and a wrong display. So, I think, the 180 Ohm is a good value to start...
I hope it helps!
All the best!
Axel
My BD dealer don´t know about a ver. 2 schematic. It might be a different software but basically the same schematic.
Eric, your idea with a not working tester was right
The tester does not work with the Low Fuel LED. We just checked the Low Fuel led in combination with my EHC58E at a bike. A 180 Ohm / 1 Watt resistor will help to switch off the led if the tank is full. This might work for the other harness replacement solutions what are on the market. I already added it in my EHC in order that there is no additional resistor required. I attach the EFI schematic with a handmade drawing. The resistor is hanging between B32 and B40 and you might can put it in the B-connector or somewhere beside of the tach board.We tested several resistances and the led was almost off with a 180 Ohm value. When you increase the resistor then the led will start to glow brighter. A value below 180 Ohm will result that the led will not glow. However a lower resistor value will increase the current through the temp sensor what will might result in a temperatur increase of the sensor and a wrong display. So, I think, the 180 Ohm is a good value to start...
I hope it helps!
All the best!
Axel
Cool!
Measure twice cut once. Haha
Axle,you may want to reach out to Big Dog let them know their EHC tester doesn't work right. Hahaha
Sent from my 831C using Tapatalk
Measure twice cut once. Haha
Axle,you may want to reach out to Big Dog let them know their EHC tester doesn't work right. Hahaha
Sent from my 831C using Tapatalk
Last edited:
Jwooky
Well-Known Member
The red went to power
Jwooky
Well-Known Member
I'm confused why you tied this to a power circuit, as opposed to just having the resister inline.Hi Fourbar,
My BD dealer don´t know about a ver. 2 schematic. It might be a different software but basically the same schematic.
Eric, your idea with a not working tester was right
View attachment 32019
We tested several resistances and the led was almost off with a 180 Ohm value. When you increase the resistor then the led will start to glow brighter. A value below 180 Ohm will result that the led will not glow. However a lower resistor value will increase the current through the temp sensor what will might result in a temperatur increase of the sensor and a wrong display. So, I think, the 180 Ohm is a good value to start...
I hope it helps!
All the best!
Axel
Can you explain?
I think the thermister gets warm and measures the increase in temp as fuel goes down?
Needs to have a set temp to use as its base or else variations in outside temps would dictate the light moreso than the actual gas in the tank?
Yes, no? I'm just guessing here so I should prob shut the duck up
Sent from my 831C using Tapatalk
Last edited:
Axel
Active Member
I have checked the line between A22 and B40 at an original EHC with an Ohmmeter and there was just a cross connection. That´s why I think a pull up resistor is more similar to the original. However, we have not removed the gasoline in the tank in order to check the resistor difference at the thermistor and see if the led will start to glow yet and I don´t have a thermistor for testing. So, we might need to play with the resstor value. Does anybody have a thermistor and an Ohmeter available and can check the resistance at room temperature? This will reduce the time for play...
All the best!
Axel
All the best!
Axel
Rottweiler
Well-Known Member
I got mine in the mail today. Will try and get it on the bike this weekend. Looks likes rain for the next 4 or 5 days. So maybe not??
Thanks Axel
Thanks Axel
Last edited:
Jwooky
Well-Known Member
I tend to agree. It perplexes me. Why would the fuel be a different temp than the air? Especially in a condition like sitting overnight in the garage.
I could see with engine heat and the fuel started dropping below the sensor you could see a deferential over short time. But then once it's completely below, and could sit and the temp equalize, how would that work?
Jwooky
Well-Known Member
I'm also not going to ask why you are sticking your hand in a bucket of gas...lol
That's because your 98.7 and the gas was prob less than that. Then once you remove it there is the evaporative cooling affect.
Makes sense to me!Google thermistor and get your hands around it.then explain it to the rest of us
When a thermistor is driven by a voltage source, it heats up. If submerged in a liquid, its temperature, and therefore its resistance, will remain relatively constant—as long as the liquid temperature remains relatively constant. If the liquid level drops, however, the thermistor becomes exposed, the heat dissipating effect of the liquid vanishes, the temperature rises, and—for a positive-TC element—the resistance increases.
The rest is bla
http://www.analog.com/library/analogDialogue/archives/43-02/level_sensing.html
Sent from my 831C using Tapatalk
Well Kevin I copied that from google. I'm not that smaht..hahaholy crap! you guys know your shit! how the hell do you know something like that!?
A little more technical but I did try to say the same thing in post #252.
Sent from my 831C using Tapatalk
Ker and I had a chat today. I've been doing my research today I've now gotten my hands around the terrible install on the PDM and I got some other electrical information I need to post.
Sent from my 831C using Tapatalk
Cool!
Hey Axle!
Got a question for you buddy. I see you are sending fuses out with your EHC. Is that a 30 or 40 amp fuse? That for power into the EHC?
Also, what are your thoughts on the circuit breaker used on the 05+ dogs? Those breakers only protect the VR from a Battery Spike the way they are designed. Best to replace with a 40 amp fuse to get 2-way protection?
I'm just trying to figure out why BD ran a breAker that won't protect the battery from overcharging?
They had a recall due to bad VR in 05 put a fuse in. Next year 06, they go back to the breaker, albeit with better VR but still lack any protection from a bad VR.
Sent from my 831C using Tapatalk
BadDawg Bill
Well-Known Member
All I've got to say is Axel is one smart dude! My fathers name was Axel and he was a genius too. I can't believe someone could spend this much time on a project and see it through. A lot more patience than I have. Go for it Axel and I hope you make a lot of $$$$.
BWG56
Guru
A guy with a name like that is just going to keep things rolling, no pun intended
and he sure did
in a very short period of time
BWG56
Guru
That's old school Buddy, and an old paint brush scrubbed the crud away