Lost Power '02 FJR

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Sunnyorlando

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Winter Park,Fl
I'm working on an '02 FJR that was running but missing. We started troubleshooting some fuel and ignition posible issues.
While doing this, we saw that the battery was getting weak so we swaped with a new battery. The new battery is 100%.
We installed it and From that point forward we have not beenable to get power anywhere on the instrument panel, lights or anywhere else. In checking the circuits I can trace power to the connectors at the instrument panel and through multiple points throughout the bike with the key on or off. But turning the key does not power the instrument panel.
I have checked (unplugged and plugged back in) all the connections I can find, and tested power throughout.
I have a wiring diagram and I'm trying to trace and see where there may be something I'm missing, a loose connection or a broken connection, or even a hidden fuse somewhere, though I can't find anything else other than what's in the fuse box.
I have checked every single connector and fuse around the bike and I don't see anything wrong - except, I am finding 12V readouts in more places than I think there should be, but I don't have a service manual to do any troubleshooting at this level, although I'm willing to do it.
I'm just thinking that there's 12 volts in places that there shouldn't be, but I could be wrong. One example is in the rectifier, there's 12V coming in on the red and the black. I'm thinking there may be a loose or broke ground and power is bleeding through. But at least the grounds I can see are good. Other the the direct ground to the engine from the battery, where is the main ground for the harness? I have not found it.
Ground to the engine is good, clean and solid.
Aside from that, I'd like to know if there's a 'typical' '02 FJR issue with this that I should look at.
Please remember - This bike was running until we swapped the battery, and that's where this started.
Any suggestions?

Thank you!
 
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I'm working on an '02 FJR that was running but missing. We started troubleshooting some fuel and ignition posible issues.
While doing this, we saw that the battery was getting weak so we swaped with a new battery. The new battery is 100%.
We installed it and From that point forward we have not beenable to get power anywhere on the instrument panel, lights or anywhere else. In checking the circuits I can trace power to the connectors at the instrument panel and through multiple points throughout the bike with the key on or off. But turning the key does not power the instrument panel.
I have checked (unplugged and plugged back in) all the connections I can find, and tested power throughout.
I have a wiring diagram and I'm trying to trace and see where there may be something I'm missing, a loose connection or a broken connection, or even a hidden fuse somewhere, though I can't find anything else other than what's in the fuse box.
I have checked every single connector and fuse around the bike and I don't see anything wrong - except, I am finding 12V readouts in more places than I think there should be, but I don't have a service manual to do any troubleshooting at this level, although I'm willing to do it.
I'm just thinking that there's 12 volts in places that there shouldn't be, but I could be wrong. One example is in the rectifier, there's 12V coming in on the red and the black. I'm thinking there may be a loose or broke ground and power is bleeding through. But at least the grounds I can see are good. Other the the direct ground to the engine from the battery, where is the main ground for the harness? I have not found it.
Ground to the engine is good, clean and solid.
Aside from that, I'd like to know if there's a 'typical' '02 FJR issue with this that I should look at.
Please remember - This bike was running until we swapped the battery, and that's where this started.
Any suggestions?

Thank you!
The "12 volts everywhere" suggests it's the ground wire from the battery that's not got continuity. Measure the voltage between battery negative and frame.
 
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The "12 volts everywhere" suggests it's the ground wire from the battery that's not got continuity. Measure the voltage between battery negative and frame.
Thanks - Yep, checked that at too. I have 12V between battery and frame in multiple locations, as well as good continuity from the Neg wire to many points on the frame and engine. I've also removed, cleaned and remounted the NEG to motor ground wire just in.
The weird thing about this is now it just stared by swapping the battery. So I went back to the original battery after giving it a good charge, and I also used a backup car battery I have for weak battery situations - nothing.

Another question I'm thinking of - would a bad ECU cause to lose power around the bike altogether? I'm thinking not - but not sure. I'm thinking that with a bad ECU I would at least get the lights and instruments to light up, but that the ECU would/could prevent starting; but not disallow power to be on the the rest of the bike. Is this a correct assumption?
 
Might look at this:
https://www.fjrforum.com/threads/lost-power-to-dash.132168/
Also, check out the ignition key switch. There were some issues...
I did that too, I even bypassed it and jumped the connectors on the bike side of the harness. Nothing.
The post referred to above has at least dim lights on turn signals. I have nothing.
I did unplug, clean and replug ever accessible connector as suggested above - nothing.
 
...
Another question I'm thinking of - would a bad ECU cause to lose power around the bike altogether? I'm thinking not - but not sure. I'm thinking that with a bad ECU I would at least get the lights and instruments to light up, but that the ECU would/could prevent starting; but not disallow power to be on the the rest of the bike. Is this a correct assumption?
Bad ECU couldn't give you 12V at the RR negative terminal. That can only be a ground discontinuity somewhere.
 
That what I thought... so, how many grounds am I dealing with on this bike and where are they aside from the obvious battery to engine?
Where are the locations of the spider ground that I read about issues with? I did look at the spider grounds post with the pics, but I cannot find those in the areas pointed to.
 
That what I thought... so, how many grounds am I dealing with on this bike and where are they aside from the obvious battery to engine?
Where are the locations of the spider ground that I read about issues with? I did look at the spider grounds post with the pics, but I cannot find those in the areas pointed to.
The ground "spiders" are, for the most part, an issue with Gen II. Not to say that you can't have a ground-related problem with Gen I but the specific spider connector issue these threads discuss is all about Gen II. (Seems that Gen III+ have a similar connector but I haven't read about associated failures.)
 
Guys - thanks for the quick replies.

I was informed in the other FJR forum that G1 does not have ground spider - and good to know G1 did not have spiders, thus why I couldn't find them.
I had already done most of the work suggested by the feedbacks.

Now - I just figured it out!
I have to say, amateurs should stay away from wiring, eves a bulbs...
So, the previous owner, in his infinite wisdom, decided to replaced a section of the ground wire that goes from the battery to the front of the bike. The OE wire is like a black 16g or 14g with a white connector that runs along the R side of the bike I to the harness under the steering head.
This section that he replaced for some unknown reason, was replaced with a RED wire.
When we reconnected the battery, of course my friend connected the Red to + as normally one would be expected to do.
I figured this out by finding that I was getting power and some of these ground points that I shouldn't be. But nothing shorted. when I saw that red wire connected to a black wire, I just figured I'd disconnect that and test and some of my power went off of the ground wires around the bike. So... I did a quick test to the negative terminal and the bike lit up, instruments, lights, etc.
Fortunately nothing got shorted or damaged. Problem solved.
When I do electrical work I try to match colors to colors as close as possible, and never would I use a red for ground and this mixing of a red wire to a black wire - is prone to cause problems like these especially when you have somebody else working on your bike.
Bottom line is that there was power being fed to ground - but didn't see this one coming.

Thank you all for the quick replies
 
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