No beep at key turn after boat upgrade

[WICKER55]

I have just completed a full restoration of a 2009 Legend Xcalibur with a Mercury 60hp EFI Which involved the dash out and wiring harness disconnected. Upon turning the key to test everything, I noticed there was no warning beep for one or two seconds as there normally is. Turning the key further will engage the starter on the motor and it will start up. I figured the warning buzzer must be defective so I took it out and powered 12 volts directly to it an it buzzes. There is power going to the buzzer when key is turned but no ground on the tan/blue wire. Scratching my head..

 

[Bondo]

I have just completed a full restoration of a 2009 Legend Xcalibur with a Mercury 60hp EFI Which involved the dash out and wiring harness disconnected. Upon turning the key to test everything, I noticed there was no warning beep for one or two seconds as there normally is. Turning the key further will engage the starter on the motor and it will start up. I figured the warning buzzer must be defective so I took it out and powered 12 volts directly to it an it buzzes. There is power going to the buzzer when key is turned but no ground on the tan/blue wire. Scratching my head..

Ayuh,..... The sensors provide the ground to sound the buzzer,....

 

[WICKER55]

How does the buzzer get a ground to sound when buzzer you turn the key, that seems to be what I’m missing.

 

[WICKER55]

With an ohm meter I get continuity between the purple wire and the tan wire which feed the buzzer. I also get continuity between the tan/blue wire and the hull of the boat as well as continuity between the purple wire which feeds the buzzer and the hull of the boat (even with the wiring harness disconnected from the engine. Could it be I pierced the harness some where with a screw when reassembling. If so wouldn’t it blow a fuse some where when you turn the key on?

 

[WICKER55]

If I disconnect battery from boat, I no longer get continuity between tan/blue or purple wire and the hull of the boat but I still get continuity between the two wires.

 

[alldodge]

The buzzer is powered buy the purple wire directly to it. So when the key is ON it has full time 12V to one side. The other side is connected to the Tan/Blue wire which goes to the oil pressure switch and the Temp switch.

When the motor is OFF the oil switch is closed and applies a ground to the Ten/Blue, so when key is turned ON the buzzer turns ON. Once motor starts, oil pressure increases and the switch opens removing the ground.

Find your oil switch

 

[WICKER55]

Does anyone know where I can find a wiring schematic for the harness for a 2007 Mercury 60 hp EFI serial # IC067126

 

[alldodge]

Not an OB guy but would suggest contacting Mercury and ask them what manual is used. I believe its 90-899975 in the link below

Being a 555ECM it should be the same as the Mercruiser with slight part differences. If you have a 10 pin connector the the wiring should be the same

https://www.mercruiserparts.com/bam/subassembly/28219/13478/0