TM 1-1520-238-T-7 11–314 11–77. 26 VAC EXCITATION XFMR 2 NO-GO AFT AVIONICS BAY – 11–77 APPEARS ON HOD (cont) 8. (ACB) Check for 26 VAC between (A342): J3–9 and J3–10. Is voltage present? YES Go to step 10. NO Replace isolation transformer/filter assembly box (TM 1-1520-238-23). 9. (ACA) Check for short between P499–A11 and ground. Does short exist? YES Repair shorted wire between P499–A11 and P686–56. Go to paragraph 11–23. NO Go to step 13. 10. (ACB) With P686 connected, check for short between A707–56 and ground. Does short exist? YES Go to step 16. NO Go to step 11. 11. (ACB) Detach P686. Check for short between P686–56 and ground. Does short exist? YES Repair shorted wire between P686–56 and P694–9. Go to paragraph 11–23. NO Replace filter adapter (TM 1-1520-238-23). 12. (ACA) Check for short between P493–A1 and ground. Does short exist? YES Repair shorted wire between P493–A1 and P220–6. Go to paragraph 11–23. NO Go to step 14. 13. (ACA) Detach wire from (A323): TB3–7–A and TB3–7–R. Check for short between wire end (A323)TB3–7–A and ground. Does short exist? YES Repair shorted wire between (A323): TB3–7–A and TB2–1–G, TB2–1–F and J5–A11. Go to paragraph 11–23. NO Go to step 15. 14. (ACA) Check for short between P493–A3 and ground. Does short exist? YES Repair shorted wire between P493–A3 and J219–1. Go to paragraph 11–23. NO Go to step 17. 15. (ACA) Check for short between wire end (A323)TB3–7–R and ground. Does short exist? YES Refer to paragraph 11–88. NO Repair shorted wire between (A323): TB3–7–C and J4–A9, TB3–7–D and J4–A11, TB3–7–N and J4–A17, TB3–7–E and J4–A13, TB3–7–F and J4–A15, TB3–7–G and J4–A1, TB3–7–H and J4–A3. Go to paragraph 11–23. 16. (ACB) Check for short between P694–1 and ground. Does short exist? YES Repair shorted wire between: P694–1 and P445–B1, J445–B1 and J233–1. Go to paragraph 11–23. NO Go to step 18.