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Alternator not charging battery


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The rain has come out today on the river lee and my solar is barely adding anything to my battery bank. 

 

So I started my engine but my batteries remain at 12.2. I left them charging for an hour but they barely went up, perhaps to 12.21, which I figure is due to the solar.

 

So I've taken a look at the alternator and seen what could be a broken connection. I am slightly worried about fiddling with wires so I filmed it and would like to call upon your expertise.

 

I hope you can make out the broken connection, I've tried to film the cabling system as best as I could but i couldnt see the screen whilst recording. 

 

Any advice would be much apreciated, hope to fix this before my fridge switches off :)

 

 

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Does the warning light for the alternator come on and stay on, go out with reving or not come on at all? Does the rev counter work?  If your voltage is showing 12.2 with solar connected then your batteries are probably at or less than 50% charged. Too much further taken from them will be bad for their long term health. I would turn off the fridge now.

Is there any wire with an exposed ends that look like it has come out of the blue connector?  There should be small wires going from the alternator D+ to the warning light and from the W terminal to the rev counter.

Experts will be along soon or you could do a search. This issue comes up a lot.

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Hey, yea there are two wires that seem to have been disconected, i'm attempting to upload a new video showing them clearly but my signal is weak here.

 

I want to attempt to plug the cables together to see what happens, but I'm a bit skeptical of touching wires without having a clue what they are...

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4 minutes ago, JCheetham said:

I'm a bit skeptical of touching wires without having a clue what they are...

This is a sensible precaution.

Where are you reading the battery voltage? Do you have a multimeter and know how to use it to trace the wiring?  What's the answer to the question re the warning light?  Without the connection to the light, and a good bulb, most alternators don't work.

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It’s quite hard to see what is going on in the video. There seem to be various wires not connected to anything! I would imagine that the green/Black wire has pulled out of the crimp terminal that is on the big stud. The black wire with blue splice crimp I don’t think is related to that wire. Maybe another one, or maybe it’s a legacy wire.

 

Anyway, as asked, what happens with the alternator light (or lights, some Beta engines have two alternators and two warning lights). The light should illuminate when the ignition is on before actually starting the engine. If it is not on, the alternator won’t start to work. Then after starting, the light should go out. If it remains on the alternator isn’t working.

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what a rat's nest! The disconnected splice seems to be connected to D+, that's the small push on terminal sitting in a rectangular hole in the back of the alternator. Confirm that this is the case. If so the alternator will not cut in without it and there is your problem. Now cut off the blue splice and strip the wire. Identify the B+ terminal on the alternator. Now start the engine and BRIEFLY touch the stripped end to the B+ and presuming the alternator is healthy it will cut in and continue to charge until the engine is stopped.

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Hey, 

 

Luckily for me a neighbour managed to come and fix it, the cables had been disconnected because they were too short and couldn't withstand the vibration..

 

wierdly the warning light wasn't staying on despite this problem existing.. which makes me think the warning light is broken. Never ending to do list hey..

 

thanks a lot for all the help :)

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10 minutes ago, JCheetham said:

Hey, 

 

Luckily for me a neighbour managed to come and fix it, the cables had been disconnected because they were too short and couldn't withstand the vibration..

 

wierdly the warning light wasn't staying on despite this problem existing.. which makes me think the warning light is broken. Never ending to do list hey..

 

thanks a lot for all the help :)

Take some decent photos of all the connections on what ever you can see,  you may find em handy one day if something like this happens again.

Edited by Robbo
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9 minutes ago, JCheetham said:

Hey,

 

Luckily for me a neighbour managed to come and fix it, the cables had been disconnected because they were too short and couldn't withstand the vibration..

 

wierdly the warning light wasn't staying on despite this problem existing.. which makes me think the warning light is broken. Never ending to do list hey..

 

thanks a lot for all the help :)

The warning light won't work with that connection broken.

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If you have two alternators, like I have, I have one big yellow warning light that works with the engine battery/alternator and a small red dot light in the voltmeter gauge which excites the domestic alternator. If I ever get the display panel off I intend to swop them as the voltmeter shows engine battery volts so having the engine alternator light makes sense to me but not my builder.

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2 hours ago, Detling said:

If you have two alternators, like I have, I have one big yellow warning light that works with the engine battery/alternator and a small red dot light in the voltmeter gauge which excites the domestic alternator. If I ever get the display panel off I intend to swop them as the voltmeter shows engine battery volts so having the engine alternator light makes sense to me but not my builder.

Why not swap the wires at the alternators?

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