Wiring questions for those who have redone theirs.

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kstills
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B190 Year: 1996

Wiring questions for those who have redone theirs.

Post by kstills »

Jump ball on whether this should be here or in electrical, however this is more a 'tear out and replace' question more than a 'how does it work' question.

I wanted to pull the generator switch off the PS wall and route it over to my new DS control panel (pending, lol). However, one wire (white, I'm assuming neutral however I'm a novice with 12v) is actually spliced into the main trunk line going through the wall towards the stove hood, HW heater starter and what I assume is the outside lights.

I can certainly cut and cap that trunk line and run a splice on the other side into the same wire, but before I did I wanted some in put from folks who've done this before.
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skater
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B190 Year: 1991
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Re: Wiring questions for those who have redone theirs.

Post by skater »

12 volt is terrible with wiring colors, it's always best to check with a multimeter. I don't trust wiring colors for 12 volt.

I always assumed the generator starter connection was specific to the generator (because there's one on the generator itself). But I guess it could be a standard 12 volt connection, and when the generator "sees" 12 volts at that connection, it fires up the starter. Quick edit: The actual starter for the generator draws power from a separate heavy wire from the coach battery, and if that wire stops carrying 12 volts, the generator shuts down.

I can tell you there will be a wire going from behind the house fuse panel to the fridge, with a relay that triggers only when the engine is running. That's the 12 volt line for the fridge. As you noted, there would also be a wire or wires for the stove light and fan, lights above the couch, bathroom light, and bathroom fan. You can see some of those in my pictures.

Also, there is a wire that comes from the monitor panel, drops outside through the hole everything else uses, and runs to the propane tank. In mine it is orange, I think. I only mention it because it's in the vicinity of some of the other wires.
1991 Airstream B190 - bought, 2005; sold, 2011; bought 2017
1995 Airstream Excella 30' trailer

WBCCI #13270, Washington, DC Unit
kstills
Seasoned Traveler
Posts: 126
Joined: Thu May 26, 2022 1:02 pm
B190 Year: 1996

Re: Wiring questions for those who have redone theirs.

Post by kstills »

skater wrote:
Wed Aug 17, 2022 9:57 am


I always assumed the generator starter connection was specific to the generator (because there's one on the generator itself). But I guess it could be a standard 12 volt connection, and when the generator "sees" 12 volts at that connection, it fires up the starter. Quick edit: The actual starter for the generator draws power from a separate heavy wire from the coach battery, and if that wire stops carrying 12 volts, the generator shuts down.

Not sure what you mean here. The switch for the gennie is definitely on the 12v trunk, which I think is what your edit is getting at. And based on that, I assume I can cut out that splice, splice back the trunk line and move the switch over to the DS panel where I would have to splice it back onto that white wire?

That about it?
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skater
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B190 Year: 1991
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Re: Wiring questions for those who have redone theirs.

Post by skater »

kstills wrote:
Wed Aug 17, 2022 11:38 am
skater wrote:
Wed Aug 17, 2022 9:57 am


I always assumed the generator starter connection was specific to the generator (because there's one on the generator itself). But I guess it could be a standard 12 volt connection, and when the generator "sees" 12 volts at that connection, it fires up the starter. Quick edit: The actual starter for the generator draws power from a separate heavy wire from the coach battery, and if that wire stops carrying 12 volts, the generator shuts down.

Not sure what you mean here. The switch for the gennie is definitely on the 12v trunk, which I think is what your edit is getting at. And based on that, I assume I can cut out that splice, splice back the trunk line and move the switch over to the DS panel where I would have to splice it back onto that white wire?

That about it?
Okay, let me back up, I was typing that quickly and avoiding work.

The main 12 volt power source for my generator is a rather heavy wire that splits off under the hood right after the fuse for the coach battery - which makes sense, it's running a rather heavy duty starter motor. If you have the generator running and disconnect that wire, the generator shuts down. It has constant power. The two start switches, the one on the generator and the remote switch, both must trigger a relay within the generator to run the starter...which also makes sense. Just like a car, the ignition switch in the steering column doesn't actually handle all of the current going to the starter.

What I was trying to say was that I always thought the harness for the remote switch for the generator (the one mounted by the sink) was specific to the Onan generator, and wasn't just a regular 12 volt wire. I'm pretty sure it's a 6-wire harness, or something like that - I haven't looked in a LONG time. Mine has an hour meter in that panel with the start switch, but that meter hasn't worked since the generator was replaced, so it's possible I'm correct about the original generator, but it was simplified for the newer version my van has now. The generator replacement was done by a Cummins shop, not me, so I don't know exactly how it's wired.
1991 Airstream B190 - bought, 2005; sold, 2011; bought 2017
1995 Airstream Excella 30' trailer

WBCCI #13270, Washington, DC Unit
kstills
Seasoned Traveler
Posts: 126
Joined: Thu May 26, 2022 1:02 pm
B190 Year: 1996

Re: Wiring questions for those who have redone theirs.

Post by kstills »

skater wrote:
Wed Aug 17, 2022 11:50 am
kstills wrote:
Wed Aug 17, 2022 11:38 am
skater wrote:
Wed Aug 17, 2022 9:57 am


I always assumed the generator starter connection was specific to the generator (because there's one on the generator itself). But I guess it could be a standard 12 volt connection, and when the generator "sees" 12 volts at that connection, it fires up the starter. Quick edit: The actual starter for the generator draws power from a separate heavy wire from the coach battery, and if that wire stops carrying 12 volts, the generator shuts down.

Not sure what you mean here. The switch for the gennie is definitely on the 12v trunk, which I think is what your edit is getting at. And based on that, I assume I can cut out that splice, splice back the trunk line and move the switch over to the DS panel where I would have to splice it back onto that white wire?

That about it?
Okay, let me back up, I was typing that quickly and avoiding work.

The main 12 volt power source for my generator is a rather heavy wire that splits off under the hood right after the fuse for the coach battery - which makes sense, it's running a rather heavy duty starter motor. If you have the generator running and disconnect that wire, the generator shuts down. It has constant power. The two start switches, the one on the generator and the remote switch, both must trigger a relay within the generator to run the starter...which also makes sense. Just like a car, the ignition switch in the steering column doesn't actually handle all of the current going to the starter.

What I was trying to say was that I always thought the harness for the remote switch for the generator (the one mounted by the sink) was specific to the Onan generator, and wasn't just a regular 12 volt wire. I'm pretty sure it's a 6-wire harness, or something like that - I haven't looked in a LONG time. Mine has an hour meter in that panel with the start switch, but that meter hasn't worked since the generator was replaced, so it's possible I'm correct about the original generator, but it was simplified for the newer version my van has now. The generator replacement was done by a Cummins shop, not me, so I don't know exactly how it's wired.
Ah, gotcha. Yeah, it's six wires, the reason I thought it was part of the 12v system was that it's run in the 12v trunk line that has the armored cable on it, and it's spliced into one of the 12v wires, unless that one isn't part of the system either.
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