TM 1-1520-238-T-6 9–335 9–120. EXT LT/INTR LT EDGE-LIGHT – DOES NOT LIGHT 9–120 Tools: Nomenclature Part Number Tool Kit, Electrical SC518099CLA06 Repairer’s Multimeter, Digital AN/PSM-45 Personnel Required: 68X Armament/Electrical Systems Repairer One person to assist References: TM 1-1520-238-23 Equipment Conditions: Ref Condition TM 1-1520-238-23 Non-transparent barrier removed WARNING Turn off power before detaching or attaching wires and connectors. High current 28 VDC or 115 VAC is present. Failure to do so could result in death or serious injury. 1. Check for 5 VDC between (A326): TB1-28-D and TB1-28-K. Does open exist? YES Go to step 4. NO Go to step 2. 2. Check for 5 VDC between (A326): TB1-28-A and TB1-28-G. Does open exist? YES Replace terminal board (A326)TB1-28 (TM 1-1520-238-23). NO Go to step 3. 3. Check for open between: (A326)TB1-28-A and P109-DD, (A326)TB1-28-G and P109-HH. Does open exist? YES Repair open wire. Go to paragraph 9–113. NO Replace multi-channel dimming controller (TM 1-1520-238-23). 4. Check for open between (A326)TB1-28-D and P100-B9. Does open exist? YES Go to step 5. NO Go to step 6. 5. Check for open between: (A326)TB1-28-D and (A326)R22-3, (A326)R22-1 and P100-B9. Does open exist? YES Repair open wire. Go to paragraph 9–113. NO Replace resistor (A326)R22 (TM 1-1520-238-23). 6. Check for open between (A326)TB1-28-K and P100-B10. Does open exist? YES Repair open wire. Go to paragraph 9–113. NO Replace pilot EXT LT/INTR LT panel (TM 1-1520-238-23). END OF TASK