Re: Still have current when ignition is off


The red signal (-) tells you that the bonding system is connected to the house bank 24 volts. In the case where nothing has ever been modified on an A54 this can be:
  1. Leaking seal in a macerator pump can show - or +. It is easy to check one at a time by removing the yellow/green wire on the macerator pump.
  2. The Mastervolt alternator body is in contact with the engine block. This happens because one of the nylon insulators or washers has cracked or is missing. If your Volvo was serviced by a Volvo mechanic, when tightening or replacing the belt, will remove these and throw them away.
The house bank 24-volt has zero connections to the Onan unless someone has connected the 12v and 24v negatives. Sometimes this connection is part of installing a Victron charger with dual charge zones. Internally, Victron has a connection between the 2 negatives.

Of course, there are many other possibilities, I am just giving you the most common.


CW Bill Rouse Amel Owners Yacht School
720 Winnie, Galveston Island, Texas 77550 

On Wed, Jul 13, 2022 at 11:18 AM CARINA HAMMARLUND <syultimo@...> wrote:

Hi Bill

we put the plus cable from the multimeter, on top of the sensors we have two cables and it doesn’t matter which one we choose or which sensor we measure on (heat sensor, exhaust sensor on the pipe or water sensor or the oil pressure sensor) the minus we take from the frame of the main engine.
we have had no one onboard installing anything (except changed the AIS). 

if we turn the controll swith on the panel for the bounding we have a clear red signal on minus but not on the plus.

SV Ultimo
Amel 54 No 165

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