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Accidentally reversed polarity!

benjdow

New member
I have a 2000 Advantage 21 SR BR, with a Mercruiser 350. So I was hooking up the battery in my boat and I accidentally reversed the polarity. There's 2 batteries and a Perko switch. I located the circuit breaker. It's the little red button that says "press to reset" well I pressed it, and nothing happened. It doesn't even feel like pressing it does anything as it really doesn't push in far or make a clicking noise. I've looked for a fuse panel, but can't find one anywhere. Can anyone help me?
 
Pressing "re-set" may not offer you any results. It may not have tripped to begin with.

Consult your OEM service manual. If this is EFI, MPI or FI, that may be polarity sensitive, you may have damaged the module or any one of several componets.

Are your battery cables not color coded?
 
it is EFI. Long story, but I had my audio amps hooked up to one of the batteries, I only had black cable for the amp cable. I used the extra amp cable that was on the + side from the amps that I disconnected and grounded to the other battery on accident.

I don't have the service manual. Is there anything I can check before taking it to a mechanic?
 
Look at the perko switch, maybe blew it out........

do you have voltage to the starter, key switch, anywhere????
 
You may need to pull codes from the ECU/ECM!
You may also want to have the alternator tested.


As for batteries...... I'm the NAZI on boating forums relating to NEVER making direct battery connections, other than battery cables themselves!
There is no need to do this! IMO.
The rear of your MBSS (main battery selector switch.... in your case, the Perko switch), is the perfect location for any accessory connections.
This dramatically reduces the risk of incorrect battery cable or wire connections when doing R & R of batteries.
It leaves properly color coded main cables ONLY to be dealth with!


The # 1 and # 2 terminals can be considered "Un-Interruptible"!
This is schematically the same as if a direct battery connection..... but completely eliminates small terminal corrosion, as well as the typical "Rat's Nest" that we so often see at/on our batteries.
Great location for bilge pump float switch connection, and/or any pre-set radio memory, for example! (fused of course)

The "common" terminal is an "Interruptible" connection.
This is great if the power source is to be turned OFF when the boat is to be left unattended and the MBSS is turned OFF!


Hope you are able to resolve this, and have no damage!
Good luck with it.

.
 
on top of the starter is a fuseable end. May have burnt thru.

Follow the pos. cable to the starter and look for the cable end that connects to the starter.

Or there maybe a fuse on the ignition.

Or the end of the neg cable at the main ground burnt thru.

So follow the neg cable to the main ground.

Disconnect the battery and follow the cables there will be a end with a fusable end, or a fuse..

I'm betting it's on top of the starter.
 
I would also use a meter ( DVM) or test light to check where power is or is not.
will tell you if the fuse/breaker is working.
 
it is EFI. Long story, but I had my audio amps hooked up to one of the batteries, I only had black cable for the amp cable. I used the extra amp cable that was on the + side from the amps that I disconnected and grounded to the other battery on accident.

I don't have the service manual. Is there anything I can check before taking it to a mechanic?

Suggestion for ALL future and current cable installs........... If you only have "one color cable", pick up some colored electrical tape at Home Depot, Lowes or electrical supply house and color code ALL cables going to battery so this very thing will never happen again. Reversing polarity can fry most electronics and alternators or even cause a battery explosion due to what amounts to a short across the battery. RicardoMarine's statements should be etched in stone and almost made into a law......
 
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If you were to visit a good Starter Motor/Alternator shop, they can supply you with color coded, self-sealing, heavy wall, battery cable specific heat-shrink tubing.
This is NOT the thin cheap stuff..... this is the good stuff!

Cost is approximately $1.00 to $1.25 per cable end.
It is permanent, and seals the crimp/solder joint. (yes..... crimp and solder!)

images
 
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