e53. BACKUP LIGHT DOES NOT ILLUMINATE INITIAL SETUP   Equipment Conditions      Engine shut down (TM 9-2320-365-10).      Batteries disconnected (para 7-48).   Personnel Required       (2)    Materials/Parts       Packing, Preformed (Item 192, Appendix G)       Wire, Electrical, 50 ft (Item 77, Appendix D)             KNOWN INFO              1. START            TEST OPTIONS            Is continuity present through both backup light lamps?     REASON FOR QUESTION     Continuity Test or STE/ICE-R Test #91 If continuity is not present, one or both backup light lamps are faulty.        POSSIBLE PROBLEMS        Faulty backup light lamps. Faulty backup light assembly. Faulty dashboard cable assembly. Faulty WTEC II cab transmission harness. Faulty rear lights cable assembly. Faulty REVERSE WARNING relay in WTEC II VIM. Faulty WTEC II transmission ECU pushbutton shift selector. Faulty WTEC III relay K25. Faulty WTEC III transmission ECU. Circuit breaker CB70 OK. Circuit breaker CB73 OK. Both turn signals illuminate. Engine starts. Transmission reverse (R) range OK. YES Replace backup light lamp(s) (para 7-29). NO TM 9-2320-365-20-1 2-638          Change 1 NOTE Perform Electrical System Troubleshooting e1. Circuit Breaker Does Not Operate on circuit breakers CB70 and CB73 prior to beginning this task. Tools and Special Tools   Tool Kit, Genl Mech (Item 44, Appendix C)   STE/ICE-R (Item 39, Appendix C)   Multimeter, Digital (Item 22, Appendix C) References   TM 9-4910-571-12&P