TM 5-3810-306-34
TABLE 3-1. DIRECT AND GENERAL SUPPORT TROUBLESHOOTING (CONTD)
Malfunction
Test or Inspection
Corrective Action
a.
Replace/defective CPU. (Refer to page 14-4.)
Step 5. Disconnect ribbon cables from CPU main board, terminal blocks X2 and X3. Check voltages between following
test points on Main board: (Refer to page 3-67.)
MP15 and MP1
=+
5 Vdc
MP15 and MP2
=-
5 Vdc
MP13 and MP12
=+
5 Vdc
MP15 and MP18
=+
5 Vdc
MP15 and MP19
=-
5 Vdc
If OK go to Step 6.
a.
Replace/defective CPU. (Refer to page 14-4.)
Step 6. Reconnect ribbon cable to CPU main board, terminal blocks X2 and X3. Check voltages between following test
points on main board: (Refer to page 3-67.)
MP15 and MP1
=+
5 Vdc
MP15 and MP2
=-
5 Vdc
MP13 and MP12
=+
5 Vdc
MP15 and MP18
=+
5 Vdc
MP15 and MP19
=-
5 Vdc
If OK go to Step 7.
a.
Repair short circuit in external wiring of load moment indicator.
Step 7. Check voltage at console terminal block between Pin 1 and Pin 2; (Refer to page 3-68.) voltage should be 24
Vdc. If OK go to Step 8.
a.
Repair wiring between terminal block X1 in CPU and console terminal block.
Step 8. Defective Console.
a.
Replace console. (Refer to page 14-2.)
3-51
