Power loss


Information and questions on GL1200 Goldwings (1984-1987)
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DAJ
Posts: 5
Joined: Thu Mar 11, 2021 7:39 am
Location: Lexington Kentucky
Motorcycle: 1985 GL1200 LTD

Power loss

Post by DAJ »



I have a 1985 GL1200 LTD, I was riding down the road when the bike lost all power. I tried to jump it, but nothing works, instruments, lights, nothing? Are there any suggestions on what is going on?


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Maz
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Re: Power loss

Post by Maz »

Check the main fuse to see if it has blown or is corroded. It may also develop a crack in the filament that can't be seen. Check volts on each end of fuse to be sure - should be battery voltage on each end.
Maz
Ironically, Common Sense is the LEAST common of all senses!
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Rednaxs60
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Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
2014 Can-Am Spyder RT LE
1995 GL1500 SE CDN Edition (sold)
2012 Suzuki DL1000 VStrom (sold)
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: Power loss

Post by Rednaxs60 »

Check the fuses as mentioned. There are two at the battery, one on the starter solenoid, and one that comes off the battery terminal of the starter solenoid and goes to the CFI circuit. This fuse is located on the left side of the battery as you are looking at it, is a 30 amp fuse and of the dog bone variety if it hasn't been replaced. Good starting point.
"When you write the story of your life, don't let anyone else hold the pen"

Ernest
DAJ
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Joined: Thu Mar 11, 2021 7:39 am
Location: Lexington Kentucky
Motorcycle: 1985 GL1200 LTD

Re: Power loss

Post by DAJ »

First I would like to thank Ernest and Maz for getting me started on diagnosis of this problem. I found that one of the fuses, the one on positive cable and starter solenoid was blown. I didn't know that finding 30 amp dogbone fuses could be so difficult. So, a shout out to Magnum Cycles in Louisville, KY for having what I needed in stock.

I purchased several of the fuses, and replaced the one that had blown out on the bike. Went to crank up the bike, instruments came on, but fuse blew out again. Changed it one more time with the same result, when I went to start bike, fuse blew out again.

Are there any other suggestions?
DAJ
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Joined: Thu Mar 11, 2021 7:39 am
Location: Lexington Kentucky
Motorcycle: 1985 GL1200 LTD

Re: Power loss

Post by DAJ »

And thanks to Rednaxs60 also!
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Rednaxs60
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Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
2014 Can-Am Spyder RT LE
1995 GL1500 SE CDN Edition (sold)
2012 Suzuki DL1000 VStrom (sold)
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: Power loss

Post by Rednaxs60 »

Did you do the external alt mod?
"When you write the story of your life, don't let anyone else hold the pen"

Ernest
DAJ
Posts: 5
Joined: Thu Mar 11, 2021 7:39 am
Location: Lexington Kentucky
Motorcycle: 1985 GL1200 LTD

Re: Power loss

Post by DAJ »

What is an external alt mod?
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Rednaxs60
Posts: 2616
Joined: Wed Nov 18, 2015 12:44 pm
Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
2014 Can-Am Spyder RT LE
1995 GL1500 SE CDN Edition (sold)
2012 Suzuki DL1000 VStrom (sold)
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: Power loss

Post by Rednaxs60 »

The "Poorboy" mod where you install an automotive alternator on the front of the engine. If you have to ask, you don't have one installed.

Does the fuse blow as soon as you turn on the key, or after you do something else such as push the start button?

The electrical schematic illustrates how the power flow is from the battery. Theoretically goes through the red wire to the ignition switch:


The reality is the the red and red/white wires are joined together in the wiring harness as per this schematic:


This connection is located in the wiring harness directly below the fuel fill and looks like this - the one I removed from my wiring harness:


The red/white wires from the RR join together in the wiring harness just after disappearing into the wiring harness, ergo, only one red/white wire at the starter solenoid.

Getting back to the question, do you use your engine stop switch (kill switch) to stop the engine? if you do, I would take the switch cover apart and look at the engine stop switch wiring. I painted the switch housings this past year, and found one of the wires to/from the engine stop switch not connected - just a thought.

There is a test procedure in the supplement I think to test the ignition switch. Would not hurt to do this test.

On the '85 Limited Edition, there is a yellow/red and green/red wire on the starter solenoid. The yellow/red wire is from the start switch to the starter solenoid, the green/red wire is to ground through the clutch diode. When you press the start switch, the starter solenoid internal switch closes and power flows to the starter. You can try a different starter solenoid to rule out that the starter solenoid is the issue, could be shorted inside.

The clutch diode is located under the seat in the wiring harness where the saddlebag harnesses connect into the electrical system. You can take this diode out and check to determine if it is good or not.

Trying to think of possibilities.
"When you write the story of your life, don't let anyone else hold the pen"

Ernest
DAJ
Posts: 5
Joined: Thu Mar 11, 2021 7:39 am
Location: Lexington Kentucky
Motorcycle: 1985 GL1200 LTD

Re: Power loss

Post by DAJ »

It blows as soon as I turn on the key. Thanks for all of this great information. I will attempt a more thorough diagnosis tomorrow.
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Rednaxs60
Posts: 2616
Joined: Wed Nov 18, 2015 12:44 pm
Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
2014 Can-Am Spyder RT LE
1995 GL1500 SE CDN Edition (sold)
2012 Suzuki DL1000 VStrom (sold)
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: Power loss

Post by Rednaxs60 »

I would start at the starter solenoid and trace the red and red white wires. Open up the wire harness and look at these two wires. Remove the air filter casing, and follow the red wire up to the ignition switch. Check the red/white wire going to the RR.


"When you write the story of your life, don't let anyone else hold the pen"

Ernest
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