Having a problem with a drop in 12v DC. The battery is strong and turns the engine over fine and all instruments work great until I hit the kill button or turn on the lights for the instruments, at that point I get a big voltage drop. Seems like the feed into and out of the start switch is fine, I put a meter on the kill switch and had around 13 volts going in, but when I push the kill switch I can only get 7 volts on the other side. Tried a new kill switch which did not change anything. As mentioned I also get a big drop in voltage when turning on the lights for instruments, so much of a drop that the instruments stop working. This is all happening only on the port engine, starboard engine is doing fine. I looked for loose connections but all seems fine. Any suggestions on where or what to look for? Removed all wires at the battery, cleaned and reconnected, no change on doing that chore. Much appreciated, Roy Holleman m/v Knot At Work Slidell, LA Roy Holleman New Iberia, LA Office 337-896-9115

It sounds like you have a high resistance (probably corrosion) problem in the engine wiring harness. Voltage drop is small with only tiny meter current flowing, but becomes substantial when higher solenoid or instrument light current tries to flow. First place to check is the large engine wiring harness plug, somewhere between the engine and the instrument panel. Take it apart, inspect, clean and spray with Corrosion Block or equivalent. Mark Richter, Winnie the Pooh, Ortona, FL presently in Knoxville, TN Mark's Mobile Marine electrical systems >> The battery is strong and turns the engine over fine and all instruments work great until I hit the kill button or turn on the lights for the instruments, at that point I get a big voltage drop. >>