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7020 atlernator light

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CDN 400 View Drop Down
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    Posted: 15 Jan 2024 at 4:46pm
Going through my new to me 7020 and can't get the alternator light to work. With the key on and even with the alternator unplugged I have power on both sides of the light socket. Where do I start looking. I'm fairly handy but I hate electrical problems.
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steve(ill) View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote steve(ill) Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan 2024 at 4:52pm
power normally comes from the key switch to the light... then OUT to the alternator and is grounded when the motor is off ( alternator not working)... when the motor starts up, the alternator puts out voltage to PUSH BACK to the bulb and balances out the power from the switch so the light has equal voltage on both sides and does not light..

The light bulb wires should be HOT coming from the switch.. and if you check the other wire to the alternator, it should show grounded.( if the light bulb is removed, or wires pulled off the socket).... Start the motor and it should show VOLTS toward the light.


Edited by steve(ill) - 15 Jan 2024 at 4:56pm
Like them all, but love the "B"s.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jaybmiller Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan 2024 at 5:00pm
With it disconnected from the alternator, you will have +12 on both sides of the light bulb and the light will be off. That is normal. Think of the filament of the light is just a 'fancy' piece of wire all coiled up in a glass bulb, it's no different than measuring 12 volts on a long piece of wire ,say from ignition switch to  headlights.

3 D-14s,A-C forklift, B-112
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CDN 400 Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan 2024 at 5:22pm
I think I get what your saying and I think the ground is the problem, with the alt plugged in and the key on no light pull the bulb and power on both sides of the socket.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jaybmiller Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan 2024 at 5:39pm
with alt unplugged, if you ground the pin on the lamp socket that goes to alt, light should come on.
if that's true and NOT come on when connected to alt, 'bad alternator'.....sorry.
3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CDN 400 Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan 2024 at 5:48pm
You can't do much with the socket all the warning lights are in a circuit board. The circuit board looks good not burnt.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jaybmiller Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan 2024 at 5:52pm
OK, try at the alternator connector ?
course it'd help to know what alternator.
some are 2 prongs, some 4, some 5....
3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water
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