TM 10-3930-669-20 1.  ALL 24 VDC CIRCUITS DO NOT OPERATE (CONT). KNOWN INFO Main disconnect switch is on. Engine cranks but does not stay running. Wire 34 OK. Relay R2 ground wire OK. Wire 7 OK. POSSIBLE PROBLEMS Wire 26 faulty. Relay R2 faulty. Engine switch faulty. KNOWN INFO Main disconnect switch is on. Engine cranks but does not stay running. Wire 34 OK. Relay R2 ground wire OK. Wire 7 OK. Wire 26 OK. Relay R2 OK. POSSIBLE PROBLEMS Engine switch faulty. TEST OPTIONS Continuity test. STE/ICE-R #91. REASON FOR QUESTION If continuity is not present, wire 26 is faulty.  If wire 26 is OK, relay R2 is faulty. TEST OPTIONS Voltage test. STE/ICE-R #89. REASON FOR QUESTION If 22 to 24 vdc are not present, engine switch is faulty. ¬ ¬ 2-128