Ch. 77-14-00. Discrepancy: 6.6 TCAS processor stuck in air mode. Unable to test from processor or load data. Resolution: Found pin 62 recessed on Avionics Interface Unit connector. Locked in recessed pin 62. TCAS system ops checks good. All work done IAW Gulfstream GIV AMM 34-47-00. See steps for further details of w

e same location as the removed GPWS computer. Expanded the STCd EGPWS Relay Unit design to house system components. Installed this newly fabricated Avionics Interface Unit in the R/H radio rack extension, adjacent to the EGPWS computer, picking up existing structure. FAA Approved Airplane Flight Manual Supplement, SC4