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@roadracer40M .... Yes, you should see voltage coming OUT of the main switch with key on... Power going in on the red wire is good, but it has to come back out to power the bike.

Looks like pin 3, a Red/Green wire.
 

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Ed is correct...BUT

The diagram I have for the 2005 F4 1000S shows the wire to be Green with a White stripe....

This is that accuracy thing. Ed, Is your drawing year and model correct? I am fairly certain mine is, but I haven;t checked other resources, yet.

1.jpg

So, what I would do is disconnect the switch connector and test continuity between pins 1 and 3 (RED wire to GREEN wire with RED stripe) and then on the other side (wiring harness) check for voltage from pin 1 (RED wire with WHITE stripe) to any good ground...should be twelve vdc.
 

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AS for the GREY RELAY on the LEFT side...

That is the GENERAL FEE RELAY. It is responsible for porting power to the entire bike. It has a diode on the back of it that can be blown when current flow gets too high as when trying to start a bike with a low voltage battery.

1.jpg


Now, before we go rolling down this hill, I need a bit more information. Not like Rocket "needed" "THAT guy's prosthetic leg...." in Guardians of the Galaxy, but more like Inigo Montoya needed to "go back to the beginning" as Vizzini suggested in The Princess Bride.

So, here are three questions:

1. Did you test the continuity of FUSE 5?
2. Is the battery installed on its side with the negative terminal forward?
3. Are ALL of the wires attached to the battery terminals in their CORRECT location? (See picture...)

2 (2).jpg


The answers to those three questions will eliminate many of the easiest possibilities that cause most of the electrical woes that folks experience and it will give us a good foundation on which to build a solution.
 

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The diagram I have for the 2005 F4 1000S shows the wire to be Green with a White stripe....

This is that accuracy thing. Ed, Is your drawing year and model correct? I am fairly certain mine is, but I haven't checked other resources, yet.
Guilty...I just grabbed the first schematic that popped up. Thought MAYBE all MV bikes would follow same wiring color scheme (I was wrong, what I get for being lazy).

Follow Chucks information.....
 

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Discussion Starter #25 (Edited)
George et al.....thank you for all the advice! I had no continuity between 1 and 3 on the switch connector.....I sprayed wd40 into the key slot, gently blew it out with air, repeated it several times, and voila, I have continuity. Bike still dead. I then move to the general feed relay - I examine it and find a bit of a crack in the housing, so I figure water go into it and shorted it out. I carefully remove the housing and I bench test the relay....it actually works as designed! Ohms across pins 85 and 86 read 87 ohms...right where it should be. Ive ordered a new one and will replace when it shows up from across the pond. I reinstall the relay and do an in-bike test on the relay and find that there is no voltage going to pin 86 when the key is on. With the naked relay in the bike, I squeeze the points together with the key off and the bike comes to life, all dash lights on, lights on, tach does its famous sweep- ive obviously bypassed the key switch - but I know the relay is not the issue - the feed to activate the relay is the issue. I get the wiring diagram ( albeit one from a 2006, so the colors are different) and I blow it up enough , 24"x36" plotter page for these old eyes, and I trace the #3 wire from the switch, and where does it go??? to the general feed relay.

then I check the voltage to the key switch....its at 10.....odd. Every other point on the bike has checked out at 12.9 vdc. So - I have juice, I have power, I have ground- the battery and everything else is good. What I don't have is a switch leg going to relay # 20 ( general feed) to activate it. If I am low on voltage going to the switch - what should I look for? If I have continuity in the switch but no power going back to 86 on the relay - it doesn't even show 10v, the same low voltage that's going to the switch, what is the issue? Im thinking I may have continuity but the voltage is not enough to activate the relay. Any help as to why I would only have 10vdc going up to the switch and no voltage at all recorded on pin 86 of the feed relay.

when I bench tested the relay, I did hook up pins 85 to earth and 86 to positive and the relay clicked and I had continuity between 30 and 87 /87b.

cheers all
 

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You have poor continuity from the main fuse to the switch. Voltage drops (and subsequently current loss) are reducing the electrical power somewhere along the way.

Try this...run a jumper wire from the main fuse to the key switch...effectively by-passing the harness wire. It can be in parallel, meaning you don't need to remove or disconnect the original wire.

If it works then you have proven the cause (voltage drops). Next step would be to use your voltmeter with one lead on battery negative and the other to probe the wire at various points between the main fuse and the switch. You should see full battery voltage at every point along the way. when you reach the point where the voltage drops to 10 you have found where the resistance is located and can find and fix it.

Most likely cause? A broken or frayed wire holding on by just a few strands of copper.

The battery in your ohmmeter will not reveal this frayed wire resistance because there is not much current in the meter battery.
 

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Ed is going down the path that I would go.

There have been reports in the past of wiring breaking or degrading where the harness rubs on the headstock.

Back to the accuracy thing...wire color will matter as you want to find the wire that leads from your switch to your relay.

As resistance from poor wire condition goes up, voltage will drop.
 

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The wire going from terminal 3 on the key switch to the General Relay should be Grey with a White stripe. It powers the coil of the relay.

Power to terminal 1 of the key lock switch comes through a RED wire with a WHITE stripe from Fuse 7.

I would first check voltage on both sides of fuse 7. Remove the fuse and check fuse continuity with a meter. Clean the fuse contacts and give them a little squeeze with some needle nose pliers and reinstall a good fuse. Recheck voltage on both sides of the fuse.

If that doesn't resolve the power delivery to the key lock switch, then you will have to trace the Red/White wire to find the high resistance issue.
 

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Discussion Starter #29
Ed and George - thank you for the insight. Before I read your responses, I wanted to make certain it was the power feed to the switch. I took two small pieces of safety wire, pressed them into #1 and #3 of the key switch. I then connect the small wire @3 via a clip to the prong on the switch connecter. I then connected the small inserted wire into the #1 post of the key switch to the positive terminal on the battery. Turned on the switch.....and it all works, bike turns over, lights on, etc. That was done just to confirm that the switch is good. Now, after reading your advice and direction, I will head back out to the garage and check voltage on both sides of fuse # 7. And if I find that is good - I will start evaluating the wiring. I did see a spot, about 1" from the connector where the wire was a little brownish.....that may be the cause. I believe it was a myriad of items gone wrong - and the best starting point was here on the forum. I will hopefully return with good news. Thank you gentlemen.

Cheers
Doug
 

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Discussion Starter #30
there she is - down inside the harness...…at the belly of the bend in the harness, where water can sit and corrode. Thank you for all your help, input, direction and patience! My bike will be back on the road by this weekend!!!

Cheers everyone!

doug
 

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Doug I think you confused the advice Chuck gave you with my advice. Silent Service is Chuck and I am George (Number2). Make sure to book a room at the Gap and you can meet the entire entourage.
 

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Discussion Starter #32
Thanks to Chuck Ed and George for all the help . You all not only helped me, but also educated me and forced me to go outside my comfort zone. Thanks again!

Doug
 

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Hey there Doug,

I'm glad you found the culprit. Getting out of one's comfort zone is a liberating process....ask my wife! I push her out of hers all of the time....)

It is also gratifying to know that my diagnostic skills haven't been lost in retirement!

Now get that puppy back on the road and join us at The Gap this October....

All the best,
Chuck (aka: George:smoking:)
 

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I think this has been reported before...... Same location. Good job !!!
 
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