LowranceNET Red Troubleshooting

Turn the unit off and back on. Check to see if GPS is now responding. If GPS is not responding, please proceed to next step.
Ensure that the NMEA 2000 leg of the power cable is connected and the 3amp inline fuse is not blown. The NMEA 2000 leg of the power cable has a red, black, and bare wire. All three wires MUST be connected for your unit to function properly. The red wire goes to the positive side of your battery and the black and bare wires tie together and go to ground.
Insure that you have the latest software version in your unit. Press the menu button twice and arrow down to SYSTEM SETUP. Press ENTER. Arrow down to SOFTWARE INFORMATION and press ENTER. Note the version listed there. Go to the software update page and verify that it is the latest available. If not download the software from the website and update your unit. If you still get a GPS module not responding message, proceed to the next step.
Reset the unit:
Below are the instructions for the soft reset for your unit.
Soft Reset:
1. Turn unit OFF
2. Press and hold the PAGES key
3. Press and hold the PWR key
4. Release both buttons when the USA map appears
Ensure that the NMEA 2000 network is connected properly. See the diagrams below.

Or
You will need a volt meter to proceed from this point:
Not a test light, we will need the voltage readings for evaluating the problem.
On the End of the GPS cable that connects to the antenna, measure ground (-) lead on Pin 1 and red positive (+) lead on Pin 2. See the following illustration.

If the power is good (12VDC), the LGC-3000 is most likely faulty and will require service. Contact Lowrance Customer Service.
If the power is not 12VDC, proceed to next step
Unplug the T connector from the cable that connects to the back of the unit. Measure voltage on the end of that cable where it connects to the T. Measure ground (-) lead on Pin 1 and red positive (+) lead on Pin 2. See the following illustration

If 12 volts are present the T connector is probably bad and will need to be replaced. Please contact Customer Service. If 12 volts are not present proceed to the next step.
Unplug the GPS cable from the back of the unit. Measure voltage on the network connector on the back of the unit. Measure ground (-) lead on Pin 1 and red positive (+) lead on Pin 2. See the following illustration.

If power is 12 volts, the cable needs to be replaced. Please contact customer service. If the power is not 12VDC, proceed to next step.
Turn unit off and disconnect the power cable. Please note that pins 7 & 8 are main power for the unit’s sonar. Pin 7 is positive (+) and Pin 8 is ground (-). Needs 12 volts of power for unit to come on.

Test ground lead to Pin 9 and (+) red to Pin 1, this is NMEA 2000 GPS power for the antenna. See the following illustration:

If you are receiving 12 volts of power, please contact us with your test results. Your unit will need to be sent in for service. If you are not receiving approximately 12 volts of power, please proceed to the next step.
Make sure the NMEA 2000 leg of the power cable is connected, red to positive, black and shield to ground or negative. See illustration of power cable below:
Check fuse to make sure it has not blown on the NMEA 2000 leg of the power cable. Ensure that the NMEA 2000 power connections are clean and actually connected to a good, 12VDC power source. Try connecting the NMEA 2000 power wires to another power source if possible. Refer back to step 6 in this guide to check the power again. If the power connections all seem correct, there could be a problem with the power cable.
Please contact Lowrance Customer Service with specific test results.

Lowrance Customer Service
12000 E Skelly Dr
Tulsa, OK 74128-2486

Customer Service: 1-800-324-1356
Lowrance website: www.lowrance.com