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Re-started the G3X system after temporarily fixing the termination issues. System still not communicating, showing 100% communication failures

Checked CAN bus resistance at the pitch servo connector and found 120 ohms. This says only one end is terminated. Removed the terminator at the GMU connection and resistance went to open ckt. So not seeing the termination at the front of the plane. Removed the MFD to access the AHARS GSIU 25 where the front is terminated, and it does have a terminator. Checked at that connector and it shows open - not seeing the terminator at the GMU. So must be an open circuit some where.

Checked at the MFD and found 120 ohms, so it is seeing the GMU termination. Open must be forward of the MFD. Removed PFD-1 and checked, and it shows open ckt. Plugged GSU 25 back in with its terminator and PFD-1 shows 119 ohms, so it is seeing the GSU termination. Problem is between the PFD-1 and MFD. Checked at GTR 20 and found 119 ohms with GSU connected, open ckt with GSU disconnected. So open circuit is in the wiring between the GTR and MFD. Confirmed by checking the individual wire continuity and found the blue wire is fine but the white is open circuit.

Started by opening up the MFD connector as it is easier to reach and work on. By wiggling the CAN bus wires found that there was an intermittant open in the white wire connection at the MFD connector. Cut out the CAN splice connection and re-spliced it, and not have a good connection. Crimped new pins on the repaired splice and re-assembled the MFD connector. CAN bus now shows 60 ohms, so both terminations are now being seen.

Restarted G3X system. Now seeing the GTX 45R and MFD, but not seeing the GTR 20 and other LRUs. GTR 20 showing green steady light, so working but not talking. Need to do more homework.

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