Need some help! Just purchased...

[jrvanvon]

Need some help! Just purchased two new tachs for my 2002 320DA from FP Marine. They said they were exact replacements but they are not. The wiring connections are completely different. Original tachs have a 6-pin harness (only use 4 wires/pins). Can anyone tell me what the different color wires are? I have a black, blue, purple, and gray/red). My new tachs have terminal posts in the back versus a plug. The terminal posts are labeled IGN, GND, SEND, ??? (no marking). Does anyone have a clue as to what wire goes where?

Thanks!

[starboard]

I couldn't download a manual for your boat to find the wire color codes so this is what I would do. Using the "Process of Elimination" with a volt/ohm meter(VOM), IGN should have the wire that has 12 volts dc when the ignition is turned ON. GND should be boat battery ground checking with the ohm meter. SEND is the pulse signal coming from the 12 volt input side of the engine coil. The "no marking" terminal is probably the tach light so should be connected to the wire with 12 volts when the dash light switch is ON. Hope this helps.

[Summer_Wings]

Standard colors would be Black - ground, Blue - gauge lights, Purple - +on with ignition.

[jrvanvon]

Thank you Summer Wings and Starboard! I was successful installing both tachs because of this website and the excellent advice shared by users like you! Thank you!!!