I had the dash out on my 187BR with 4.3 GL-D Volvo Penta engine to change the Faria RPM gauge last year and found that the alarm/buzzer with a crimped on post connection (to the red wire) was disconnected from any type of power source. This likely would be the alarm/buzzer for engine overheat for the riser sensors, thermostat overheat, or oil pressure sensor (all wires feeding those sensors is brown with a black stripe). The one wire (black negative) which is attached to the alarm/buzzer goes to a tan with a blue stripe wire in the main wiring harness. If I attach the positive (red) wire with crimped on post connection of the alarm/buzzer it goes off constantly when attached to a 12V power source.
Anyone have any thoughts why the alarm/buzzer would constantly go off when attached to a 12V power source with the key turned to just the on position, or even with the boat running? Any idea where I could get a wiring diagram for this year/model boat and engine?
The 10 pin wire harness does have a tan with blue stripe wire in it where mounted to the engine.
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