Does anyone know if there are cables available to connect an OTC breakout box to the ecm on a Harley? I would like to use a scope to better understand how the sensors work and the timing of events. A breakout box would make it a whole lot easier. The one referred to the diagnostic manual is made by Kent-Moore, same company I believe as OTC, but they will only sell them to dealerships and my dealer won't sell one to me. So I'm looking for alternatives. I can't find a list of cables available for the OTC breakout boxes though.

 

I'm not sure if you'll be able to buy what you need. You would have to custom make one and that would be a pain, but it could be done. Probably be expensive as you would need bothe male and female ends. I know I use ours all the time, it is really a lifesaver.

 

You can get the connectors for about $3.50 each. I don't really see why the dealership won't sell them. About the only good reason I see is to keep people from hacking the ecm, but there the lack of a breakout box would hardly slow them down. It certainly doesn't hinder DynoJet, DTT or Zippers.

 

They won't sell tools because it takes money out of their service department. Hell I can't even get harley parts from the states, here in Canada. They won't ship them to me. Tried to get a fuel pressure adapter from HD. No way. Bought another tank to tb hose and made my own tool. Even though I found better prices in the states for the fuel line they would not ship it to me. HD rules. Got stuck going to my local dealer. HD has all the bases covered to keep profits high. That's also one of the reasons I went Tmax. I want control of my own bikes tune.
Ron

 

I'm assuming what you're trying to achieve is to probe key signals from/to the ECM? I don't know what the dealers break out box looks like but I assume it's a box where the ECM snake/cable connects to the box then passes through the box and back to the ECM unit. And within the box, it "breaks out" or taps into key critical ECM signals and allows you to hook a logic analyzer or diagnostic computer to the box via BNC connectors. Is this right?

Sounds pretty easy to make your own, though very tedious. However, if you're going to use it a lot, it could be worth the effort to construct. Most of us don't have a multi channel logic analyzers, but a dual channel scope are common and not "too" terribly expensive. Also if you are going to use a scope, I'd use the scope probes for two reasons. One, is that you are sure not to load down the probed signal with a high impedance scope probe and two, you can use any terminal strip to bring out the ECM signals and save the cost of BNC connectors.

Various on-line electronic stores will have the parts you need as well as Radio Shack.

Now, being a BSEE, you have my curiosity up why you want to snoop the ECM signals. Are you planning on making a new toy to sell to all Harley owners? If yes, I want in!

 

It's actually simpler than that, the box just has female holes in it to plug test leads from a multimeter into.

 

Nothing like that. Just things like how the map pressure varies during the cycle as the valves open and close or how much the engine speeds up as the cylinders fire.