electrical problem

[Ken Heyman]

When I installed my batteries this season (after winter lay-up), I turned my battery selector to "all" and -----nothing. There was no function at any of the accessory panel switches--cabin lights, nav com, running lights etc. I am suspicious that I have a corroded ground somewhere but other than the engine ground wire, I don't know where to look. I thought there was a ground panel somewhere in the engine compartment? I did remove the panel above the nav table and do some multi meter testing that was constrained by my limited electrical know-how. The wires leading to the various accessories are showing voltage.

My fuel pump, starting motor etc. are all fine as that is a separate circuit.
Probably something simple so any suggestion would be appreciated.

thanks in advance,

Ken

[Ray & Sandy Erps]

I re-did the rat's nest behind the electric panel last year.  I don't remember how the switches were supplied with the 12V power off the top of my head, but I can think of a quick test to start the trouble shooting.  If you take a little jumper wire from one of the hot poles on the battery selector switch and run it to the little jumper bars on the back of the nav panel switches and stuff works, it's probably not a ground problem, but an open circut feeding the nav panel.

If no one else comes up with the answer before I go to work tonight, I'll take a look at the electric schematic on the boat and see if I can come up with a more precise answer.

[Ted Pounds]

Ken,

It can't be the ground by the engine if the engine stuff works.  Also with the engine stuff working there must be power coming from the battery switch.  On my boat there is a ground bus (bunch of wires screwed to a terminal strip) behind the electrical panel.  It has its own wires going to the battery bank.  The engine instruments are grounded at the engine which has its own heavy duty ground to the batteries.    If yours is the same then the first place to look is those wires from the ground bus behind the panel  to the batteries.  The only other possibility, as I see it, is the power connection from the battery switch to the accessory switches.  That you can check right on the back of the panel.   I just noticed that you said the wires going to the various accessories are showing voltage; that rules out the power connection.  The next thing to check is the ground.  With the neg side of your voltmeter on the neg terminal of the battery bank turn on some accessories and check the ground bus for voltage.  If there IS voltage then the ground bus is NOT grounded and that's where your problem lies.  If the voltage is around 12 then the ground is completely disconnected.  If it's somewhat less then that  then there's a bad (corroded, loose or whatever) connection on the ground side.  Do this test with a bunch of accessories on (and make sure the accessories ie cabin lights are turned on) to make sure electricity can get to the ground side.  If there's no voltage on the ground bus with stuff on and still nothing works then move the positive probe back up the circuit until you get a voltage.  When you get a voltage then your problem is between that point and the last point where you got no voltage.  Clear as mud?  Let me know how you make out.  If you still can't figure it out feel free to call me at 815-670-1800 since I'm off work through Sunday.

[Ted Pounds]

I should mention there's also an AC bus behind the electrical panel.  The ground bus should have ALL black wires going to it.  You don't want to mess with the AC bus.  It's best to make sure AC power is off before you probe  around back there.  And that includes an inverter if you have one.

[Stu Jackson]

Ken, check the connections at the back of your 1-2-B switch, and the connections at your house bank.  It sounds like one side of your 1-2-B switch isn't making contact.  Could just be a bad switch.

Stu

[Kyle Ewing]

If a remember correctly there are two grounds to connect at the batteries, the heavy guage wire going to the engine and a much smaller wire coming from the electrical panel.  The smaller one can be easy to miss if you're not looking for it.  It may seem obvious, but did you connect both to the batteries?

Kyle Ewing
Donnybrook #1010
Belmont Harbor, Chicago

[Ron Hill]

Ken : I'll be the first to admit that I've never fully understood the (- negative) wiring in my C34.  Here's what I've done to insure a good ground connection :
1.  I have duel output alternator so I ran a positive to each battery as well as a negative #4 ground from the alternator (-) to the negative gang on the house bank batteries.
2.  This is what might help you solve your problem.  The main negative buss bar for the most (-) DC circuits is above the Perko switch in the inside back of the main electrical panel (above the nav table).  Because I don't know where this "ground terminal" (#10 wire) that Catalina talks about is/runs, so I added an extra ground wire.  I ran a (-) #8 wire from the battery compartment negative gang, under the flooring and connected it to that main negative DC buss bar.  I think if you check that out with a long jumper wire (from the battery/s to that buss bar), you'll have all of your circuits back on line.  
3.  I soldered the two wire connections (they are crimped) that are connected to the port side of the engine block.  The #4 is from the battery and the other #10 is that elusive ground terminal wire that attaches to that DC buss.  Did this early on in 1989.

Hope this helps.  

[Ken Heyman]

Thanks all for the help.

The problem was in fact the ground running from the bus behind the nav table to the battery. In a conversation with Ted, I realized that I may not have connected that ground. It, in fact, had slipped down in the battery compartment well and I had failed to connect it   . All the diagnostics however allowed me to poke around behind the panel. I was able to "clean" up change and recrimp some connections at the panel. I also moved my "accessory" hot wire to a different panel switch in that the existing connection was about to fail. I'm going to implement some of the other suggestions as a future project.

thanks again,

Ken