Shore power - 2008 302

[abtv]

Does anyone have any advice on how to fix the shore power connection on a 2008 302? The cable lights are on on both ends and when I flip on the shore power switch, the battery charger and other electronics don't turn on. Thanks!

[jhnmdahl]

Fuse? Switch? Not sure now the boat is wired, but the next step is to get a meter (or buy a case of beer for a buddy with a meter who's willing to troubleshoot) and trace the line coming in from the shore power socket. If the charger and other electronics are all off, it won't be too far that he has to trace to find the problem.

[abtv]

Fuse? Switch? Not sure now the boat is wired, but the next step is to get a meter (or buy a case of beer for a buddy with a meter who's willing to troubleshoot) and trace the line coming in from the shore power socket. If the charger and other electronics are all off, it won't be too far that he has to trace to find the problem.

OK thank you! I'm trying to locate the wiring diagrams for this boat and only have one page. Any advice on where to get them?

[jhnmdahl]

Fuse? Switch? Not sure now the boat is wired, but the next step is to get a meter (or buy a case of beer for a buddy with a meter who's willing to troubleshoot) and trace the line coming in from the shore power socket. If the charger and other electronics are all off, it won't be too far that he has to trace to find the problem.

OK thank you! I'm trying to locate the wiring diagrams for this boat and only have one page. Any advice on where to get them?

Cobalt may be able to provide you one if you call them, but if nothing's getting power you're probably better off spending your time just tracking the line from the shore power inlet to something without power, e.g. the battery charger.

The manual for your boat can be found at https://cobaltboats.com/art/manuals/2008_302_OM.pdf and there are wiring harness diagrams on p. 4-2 and 4-3, which could also be useful.

[jwill323]

Are you showing power, 120V on your breaker panel AC meter when the shore power is energized? if not, there is a breaker between the shore power and the panel.

[jwill323]

see page 3-34 on the above manual link. Shore power inlet breaker switch.

[jwill323]

so the procedure would be:

plug in shore power
make sure you have lights on the cable
turn on shore power inlet breaker to send power to the 120v panel on the boat
verify 120v on the panel meter and verify correct polarity (panel will say if this is wrong)
turn on shore power breaker on the panel (if you have a generator there is a lockout you will have to slide between generator or shore power)
then you can turn on the breakers on the 120v side of the panel to turn on what you want

[abtv]

so the procedure would be:

plug in shore power
make sure you have lights on the cable
turn on shore power inlet breaker to send power to the 120v panel on the boat
verify 120v on the panel meter and verify correct polarity (panel will say if this is wrong)
turn on shore power breaker on the panel (if you have a generator there is a lockout you will have to slide between generator or shore power)
then you can turn on the breakers on the 120v side of the panel to turn on what you want

Thank you! Where is that meter? The panel just looks like this.

Screenshot 2025-06-04 at 8.29.22 PM.png

[jwill323]

Sorry i thought you had the closed bow version which would have had an AC panel in the cabin with the AC meter on it. On the open bow version it says to just plug in the shore power and turn on the shore power inlet breaker. once you turn that on the charger should turn on. My bad on that i now see your problem! I guess i would start at the power inlet on the charger and see if you have 120V on the power leads there or at least if it lights up that its getting power. Is your charger a Charles charger? The manual also mentions on page 4-7 a note that there is an AC load center panel but unfortunately doesnt say where. I would try and locate that, I'm sure there are some breakers there which i think would likely be the issue if some of them are flipped off.

[abtv]

Sorry i thought you had the closed bow version which would have had an AC panel in the cabin with the AC meter on it. On the open bow version it says to just plug in the shore power and turn on the shore power inlet breaker. once you turn that on the charger should turn on. My bad on that i now see your problem! I guess i would start at the power inlet on the charger and see if you have 120V on the power leads there or at least if it lights up that its getting power. Is your charger a Charles charger? The manual also mentions on page 4-7 a note that there is an AC load center panel but unfortunately doesnt say where. I would try and locate that, I'm sure there are some breakers there which i think would likely be the issue if some of them are flipped off.

Thank you so much for your help with this! I truly appreciate it.

There's a panel nearby to the shore power that is black and has a few round breakers I believe, plus the metal jump start studs (see below). And across the boat, above the refrigerator, is a small black panel with 3 switches and green LEDs. One says battery charger and another outlets. Next to a GFI. When shore power is on, none of those turn green.

Screenshot 2025-06-04 at 9.32.42 PM.png

[jwill323]

The round breakers by the jumper studs is all DC breakers that's not it. The other one by the sink is what you want that would be the AC load center. If you flip those switches do you get a green light? if the switches are on and you don't get the green light try turning them off and then back on, that may reset the breaker if its been tripped. You may also want to check the GFI and see if maybe that has tripped and hit the reset button on that. I would start with that and see if you can get your green lights on.

[abtv]

The round breakers by the jumper studs is all DC breakers that's not it. The other one by the sink is what you want that would be the AC load center. If you flip those switches do you get a green light? if the switches are on and you don't get the green light try turning them off and then back on, that may reset the breaker if its been tripped. You may also want to check the GFI and see if maybe that has tripped and hit the reset button on that. I would start with that and see if you can get your green lights on.

Thank you! When I flip those switches (battery charger, outlets, etc.) they don't turn green. And I have gone back and forth with them. What's interesting is I tried pressing both the RESET and TEST buttons on the GFI and neither would push in. Does that mean it maybe needs to be replaced and would that cause the switches to not work? If so, let me know which you recommend I get. I appreciate all the insight and feel like I'm getting closer. : )

[jwill323]

yes , i think you have narrowed it down! Is this boat new to you, have you seen all of this work before? if there is no power to the switches in the load center than the problem is somewhere between the shore power inlet plug, the shore power inlet breaker or the load center. I think i would disconnect your shore power connection (make sure there is no power on the system) and I would start at the beginning and unscrew your shore power inlet plug on the boat and check the connections on the back of the inlet plug. If that looks good (all connections tight and clean)I would unscrew the shore power inlet breaker panel and check your connections on the back of that (again all connections clean and tight) if that looks good I would unscrew the load center panel and check your connections there (clean and tight). i think you will probably find the problem on one of those components. Again before you start checking the connections on any of these components make sure the boat is disconnected from shore power, you don't want to work on any of this while it is energized! If all the connections look good you would then need a multimeter and check the continuity of the cables between these components, but i suspect you will find an issue on one of these components since the connections between these are done with a marine grade romex type wire which is pretty robust. If you find loose, maybe burnt connections I would replace that component. if it all looks good then it could be a bad breaker and i would think probably the main shore power inlet breaker but i would start by checking the connections of all 3 of the components. even if you find 1 bad connection i would probably still check all 3 anyways.

[jwill323]

You may be able to crawl into the engine compartment and see some of these connections from the backside without unscrewing them depending on the exact location and your willingness to crawl through the bilge to get there. The more i think about this i think the problem is between the shore power plug and the shore power inlet breaker. The GFI not being resettable i think is just an issue with power not making it over to the load center and the GFI not having power on it. I think if the load center had a problem it would trip the power inlet breaker so that's why I think the problem is between the shore power plug and the inlet breaker. I really think the problem is the shore power plug, these have been known to break.

[jwill323]

If the inlet plug is the problem this one from Marino is a nice replacement. I put this on my boat when i swapped out from the one with the plastic cover.

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