When I say IC relay, I mean within the ECU. Not the mechanical external one.Brick said:Yamaguy55,
Great question as I've not done this yet... And want to. And will do this as I too have been thinking I need to see how the headlights will function IF I install a lighted switch between the relay to ground as my on/off switch for my headlights.
However, the relay that is not getting the ground is not an IC relay it's a full size relay that is on the side panel. It's the top left one when you take both right side covers off. Any way one of the out pins from the ECU goes to this relay providing the connection that closes the relay allowing 12 volts to the H7 bulbs that are the headlights.
So I don't believe anything is going to be reset but I'm gonna make the test anyway.
That's what I meant: there is some sort of solid state device within the ECU that changes state, and applies the ground. Essentially, it is a solid state switch, relay, whatever you want to call it. They can get stupid and hung up in one position, for lack of a better term. We use these things throughout the equipment I work on. Sometimes by artificially applying the ground with the device in circuit makes them wake up, sometimes not. Many times it is current flow. Unlike traditional mechanical contact relays, they require a certain current flow to switch states. You can have the voltage, but not the current, and they won't work correctly, or at all. One way to prove this is an external wire from the actual physical headlight relay to the connection at the ECU, with everything hooked up normally, just the additional conductor. Use something larger than standard wiring to be sure you get good amp handling ability..If it suddenly starts working, there's a bad connection or too much resistance in there somewhere. It wouldn't hurt to start pulling connectors and perhaps spray with WD40 and refit. Silicone grease would help as well. I suggest Dow Corning DC4. One tube would last you a lifetime. I use it at work and it delivers. It will prevent moisture from creating bad connections due to corrosion/contamination. Use sparingly. Works great on spark plug caps/coils: you can get them back out! (use anti-sieze on spark plug threads, not this stuff)Brick said:Yamaguy55,
Yes I knew what you mean and the relay that is not getting the ground is NOT in the ECU. I suppose there could be one IN the ECU that's not outputting the much needed ground.
Thanks I will post my findings when I run this test.
I'm lost. Start over.Brick said:Ok I made the check... I added a ground to the relay. Note I didn't go to the ECU because 1) it's a real pain to get to and not even sure I can open up the back of the connector to access the pin while its still connected to the ECU. And 2) when we had the ECU out we checked the wire between the ECU and the relay. It had 0 ohms resistance. We had also wanted to be sure that the wire from the ECU went directly to the relay and not somewhere else first.
The result = No headlight! So it didn't reset and so it's more of an indication that I need an ECU.
Come on Yamaha... come through for me!
I agree. I think the ECU is the symptom. It may also be a problem, but I don't think it started there.greg the pole said:sorry to make things even more complicated for you brick.
Did you try things the other way round with your friends bike?
Your relay in his harness etc...
Also, if you look at the wiring diagram, the relay coil has a diode between the negative (from ecu) and the positive (from accessory when bike is turned, on and running), for what purpose I do not know. It's been a while since electronics class, but if I'm not mistaken, I diode is a one way street. Allowing flow of current one way, and blocking it the other. In this case, I think it goes from negative to positive. Again, it's part of the relay, so if the relay/diode is bad, then your replacement should work...if the above conditions are right.
The way I looked at the diagram, is that if, the bike is running, you should have 12 VDC on the one side of the coil, and a ground from the ecu. You should be able to ground from the battery to the negative terminal, when the bike is on, and things should go on for you.
Failing that you can also temporarily bypass the relay, and jumper the two open contacts to see if the power goes through cleanly.
I still think this has something to do with the original wiring harness. In some instances, the damage was done beyond the headlight harness, and into the main harness.
as I said before. I highly doubt it. It's a 12V system, all components will run on said voltage, unless they have a resistor in line to drop the voltage.Brick said:Ok... guys I did replace my relay because when we checked it didn't work. AND yes I did put my ECU in my buddies bike AND the problem did move to his bike = no headlights.
Re:the relay that is external to the ECU... the one that actually turns on the headlights, well I hesitate to do any more testing on it as well... is it possible that it is a 5volt relay. I mean just the coil part that utilizes the ground output from the ECU? I don't remember why or what but at some point in this "trip" I thought it might be a 5volt relay.
I did NOT hear from any of the Yamaha people today... damn, I would love to hear from them telling me that a new ECU is on the way!