2005 GL1800 Lights Are Strobing


Information and questions on GL1800 Goldwings (2001-2017)
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BMLGoldwinger
Posts: 2
Joined: Sun Oct 07, 2018 2:46 pm
Location: Lake Orion, Mi. 48360
Motorcycle: 2005 GL1800A

2005 GL1800 Lights Are Strobing

Post by BMLGoldwinger »



I would like to request some assistance with an electrical issue I am having with my bike from the collective experience of other owners of the Gen 1 GL1800.
My bike is a 2005 GL1800 with ABS. The bike has 86000 miles on it. I have just installed a new battery so based on that fact I am assuming the battery is not the cause of the problem I am having. Also, since the battery was just recently installed, I know the battery cable to battery connections are clean and tight. The battery I replaced had been in the bike for 7 years and there had never been an issue with the performance of that battery. Also, the issue is occuring with both the old and the new battery.
The issue I am having, and this has been happening for quite some time, is the pulsing of the bikes front and rear lighting (headlights/taillights) and the dash lighting and the LED screen. Let me clarify the pulsing effect. The systems/components noted above will get brighter and dimmer (pulse) at an equal rate until, as noted, the problem corrects itself. The lighting nor any other electrical component on the bike has ever turned completely off and on when the pulsing occurs.
The pulsing normally occurs shortly after starting the bike, lasts normally several minutes a then the pulsing stops and everything with the electrical system seems to be functioning normally. Also, the pulsing is intermitent does not occur at every start-up. Does occur more often than it does not though. I have seen the pulsing occur though when the bike is fully warmed up but is not the normal occurrence.
I have checked the alternator output voltage (at the battery terminals) using a voltmeter upon starting the bike. When the pulsing effect starts the voltage at the battery will fluctuate from a low of around 13 volts up to a high of 15 volts. I have though, on occasion, seen the voltage peg my voltmeter at 16 volts which is its maximum reading.
After the bike has been running for several minutes, the idle speed has slowed and stabilized, the voltage output of the alternator will be stable at 14.5 to 15 volts.
The bike has never stranded me with a dead battery while riding it, indicating an alternator which has failed or has had a dead battery upon attempting an initial startup of the bike.
Based on a lot of internet searching I am thinking a have a rectifier that is failing but I do not want to start troughing parts at the parts trying to fix this. I also don’t want to just ignore what is going on and end up being stranded when on a trip somewhere.
I am hoping the collective group out there might be able to give me some feedback on the cause and a cure for the problem I am having.

Thank you for any insight you may be able to provide.


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Rambozo
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Re: 2005 GL1800 Lights Are Strobing

Post by Rambozo »

Sure sounds like an alternator problem. Should not be going much above 14.2 volts, either. Depending on your meter you can check for AC voltage at the alternator output. That can often show a bad rectifier or if you have extreme ripple. The best is to use an oscilloscope, if you have one.
How intermittent is it? If it repeats enough, and you have no other way to test, you can disconnect either the alternator output or the exciter lead and see if the pulsing goes away.
Right off, though if you are seeing 15 volts, something is wrong, so time to pull the alternator.
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WingAdmin
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Re: 2005 GL1800 Lights Are Strobing

Post by WingAdmin »

I would say you have a problem with the voltage regulator built into the alternator. It could be as simple as a poor connection on one of the connectors or wires.
BMLGoldwinger
Posts: 2
Joined: Sun Oct 07, 2018 2:46 pm
Location: Lake Orion, Mi. 48360
Motorcycle: 2005 GL1800A

Re: 2005 GL1800 Lights Are Strobing

Post by BMLGoldwinger »

Rambozo.
Thank you for your reply and feedback. I will use your suggestion of testing the bike without the alternator connected and see if the pulsing does not happen. If that is the case I will pull the alternator and see if I can see anything obvious with the alternator causing the condition that can possibly be repaired. If not I will be getting a new alternator and installing it prior to the riding season here in Michigan.

Brian


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