If you are holding a cut harness or looking at the back of the connector, identifying the wires is the first step. While specific year models may have slight variations, the standard Lowrance "Red Connector" pinout used on the GlobalMap 3500 series is as follows:
Match colors exactly: and Black to Black . If the provided wires aren't long enough, you can use standard speaker wire to splice and extend them. Transducer :
The Lowrance 3500 uses a black wire for positive (+) and a red wire for negative (-) . This is the opposite of industry standard. Reversing polarity will instantly destroy the unit. lowrance 3500 wiring diagram
GPS models, the power/data cable includes additional wires for communication: Yellow Wire: Transmit (TX). Orange Wire: Receive (RX). Shield Wire: Signal Ground. Blue Wire: Not used for standard COM-1 configurations. Pro Tips for Installation Prevent Interference:
The LMS-350A was one of the first combo units to output NMEA sentences (GLL, GGA, RMC). The diagram clarifies: If you are holding a cut harness or
Original Lowrance harnesses are becoming scarce. Use the wiring diagram to build your own.
For further details on mounting and alarm setup, you can consult digital archives like the Lowrance 3500 Manual on Scribd or the Lowrance Downloads Page for legacy support. Lawrance Sonar 3500 PDF | PDF | Manufactured Goods - Scribd Transducer : The Lowrance 3500 uses a black
Controls the unit's display lights. You can wire this to a separate accessory switch to control lighting independently or tie it directly to the power switch for simultaneous operation. Fuse Requirement: install an in-line 3-amp fuse