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Strange electrical issues

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At this point my Drz400sm Has no electric start, no headlight and when I hit the horn my gauge lights reset. All of these issues began with my headlight occasionally not working and then eventually it wouldn't start using electric start. I swapped a new battery into it hoping that would solve the issue and that didn't change a thing. Could this be a bad rectifier? Also my turn signals still work

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If your battery is still charged, pull apart all the connectors and spray in a bit of WD40 or similar.

If that doesn't fix it you will have to do a bit of testing with a voltmeter.

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At this point we do not know if you have a charging problem or not.  The job of the stator and rectifier is to keep the battery charged.  All of the electrical system will work normally when there is a fully charged battery regardless of the stator and rectifier.  It just will not continue to work very long without a functioning charging problem.  So lets not worry about battery charging just yet.   I think there must be more to the story than what we know so far.  Symptoms are of a discharged battery or a problem with the wiring from the battery to the loads.  Did the new battery not help at all? or did it help at first then the problem returned?  What is the new battery?  Was it put into service correctly with a full charge?  The turn signals that still work - are they original or LED replacements?

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At this point we do not know if you have a charging problem or not.  The job of the stator and rectifier is to keep the battery charged.  All of the electrical system will work normally when there is a fully charged battery regardless of the stator and rectifier.  It just will not continue to work very long without a functioning charging problem.  So lets not worry about battery charging just yet.   I think there must be more to the story than what we know so far.  Symptoms are of a discharged battery or a problem with the wiring from the battery to the loads.  Did the new battery not help at all? or did it help at first then the problem returned?  What is the new battery?  Was it put into service correctly with a full charge?  The turn signals that still work - are they original or LED replacements?



Thank you for the great reply I'll try my best to explain. So once again thanks for clarifying the purpose of the rectifier and stator since I wasn't clear on that. The battery I swapped in was straight out of a friends functioning Drz and the swap had absolutely no effect on anything. Yes the signals are led replacements so they couldn't be on a different circuit

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The point of the LEDs working is they require very little power.  They can work when nothing else will. Since the replaced battery had little affect, that narrows it to something after the battery.  There is a small connector in the red wire between the battery and the fuse.  Check that for heating and corrosion.  Next check the fuse holder.  Replace the fuse even if it looks OK.  Report your findings.

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Yes, could be but we have not gotten there yet.  If he finds no problem with the red feed to the switch. I was going to have him "hot wire" around the switch to see if that fixes anything.  He can also run a wire direct from the bat to the switch or bypass the switch to isolate the problem.

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When it seems your system suddenly has a bunch of gremlins, its the ignition switch. You can chase ghosts over hells half-acre, or change the switch. :D

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So my fuse replacing endeavor wasn't successful and I've already tried cleaning things so I'm thinking I'll give replacing the ignition switch a shot. What's this about hot wiring?

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Simply pull the wires off the ignition switch and connect them all together.  Red to Orange to Gray to Brown.  You can make a jumper wire that will plug into the connector.  If the problem goes away, it was the ignition switch.  If not, run a wire from the battery positive to the orange, gray, brown and see if the problem goes away.

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Free Power might be in the future.  Right now we are just trying to get battery power to the loads.

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Ok I'll give that a shot if I get time tonight thanks for the help! I'll let you know what happens

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I don't understand your concern here.  OP is not running the system without a fuse.  In fact he probably does not need to run the motor at all to test the switch or the switch "hot wire bypass".  The original fuse is still in place. If the OP runs a test wire direct from the battery to bypass the harness wire he is going to be standing there holding the wire.  In the event of a short the wire is going to get real hot real quick and get pulled loose.  I don't see the error of my advise.

In the original configuration the battery is fused for current in or out.  But the charging system to all the other loads on the motorcycle is not fused.

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Exactly right.  One of the benefits of Free Power is no power is lost thru a fuse or fuse connections.  Some M/C, car, truck electrical systems charge thru a fuse (or thermal breaker) and some don't.   In the event that the "Free Power" wire between the battery and the RR were to be grounded it may indeed burn up the wire.  The free power wire is out side the original wire harness so damage if any would be minimal and easily repaired.  The instructions for "free Power" say to use good quality wire and to run it in protective sleeving.  I have not heard of anyone burning up their Free Power wire in 15 years.  Only 1 person as ever posted Free Power did not work and restored the original harness connection.  We never resolved the reason why.

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I have the same problem 2 weeks ago ..BEFORE YOU BUY ANYTHING  try this, I drained my battery on a ride home from work and cant start it with the electric starter ,its good I installed a kickstarter ,the bikes running is fine and smooth , I will charge the battery and it will run good but as soon as I got home the battery is flat out .lights are all dim and no electric start  I checked everything stator and rectifier,wires,ground etc as per TT procedure,until I got fed up and replaced the stator and rectifier still the same thing  every thing checks out until I decided to cut the wire from the rectifier(2 wires with black connector) that's when I found out theres no connection between them when you check one side of the connector going to the battery theres continuity  and the other side of the connector  going to the rectifier theres continuity / current , so you will think its OK...NOOOO  Its when you plug them together  they are not making contact (AND YOU WILL NOT KNOW THAT UNTIL YOU CUT THE WIRE) and when I cut the wires to the rectifier and plug it in theres no continuity to the battery, so I did the FREE POWER MOD problem solved.

Hope this helps.

Edited by guitarmusiczone
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McMillin. For me to give advise I have to know exactly what you did. 

You replaced the fuse, right?

The new fuse is tight in the fuse holder?

Did you find and inspect the connector in the red wire between the battery and the fuse holder?

Have you run a jumper wire from the battery + to the Orange wire at the ignition switch? 

I know you tried a different battery so safe to assume the battery terminals are clean and tight?

Check the end of the battery ground cable where it attaches to the motor.  Clean and tight?

Does the taillight illuminate when you turn the key to the far right?

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On 8/18/2017 at 3:50 PM, Noble said:

1) Exactly right.  One of the benefits of Free Power is no power is lost thru a fuse or fuse connections.

2) Some M/C, car, truck electrical systems charge thru a fuse (or thermal breaker) and some don't.

1) What is the resistance of the fuse? How much power is lost? I'm willing to guess total ohms of the fuse is less than the wire.

2) I'd be interested to know which manufactures don't fuse the output. Sounds like a fire hazard and liability to deviate from established practice, which is certainly codified somewhere.

A stock system that is in proper condition is more than adequate. If there is something that the Japanese (Denso Electric, LTD) are experts at, it is vehicle wiring. Probably why they do the electrical for nearly everybody from Toyota to Harley-Davidson, with Triumph in there too. It is such a HUGE list. :D

(Shame Ducati and BMW don't run Denso)

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