TM 5-5420-226-20-1 Symptom-73 DETAILED TROUBLESHOOTING PROCEDURE FROM STEP SUPPORT SYSTEM -PERSONNEL HEATER (Continued) o²⁴ : )’^{“’Check    master    controlpanel   power    harness(CKT   400)} for   continuity. Second Technician (Operator’> Station) l   Set   PERSONNEL HEATER switch OFF, l   Set   HEATER MASTER switch OFF. ~ ~~~fq,~~ !— After disconnecting ground straps, do    not allow them to    contact any metal    surface. First Technwian (Front of   Crew Comportment) l   Disconnect three battery ground straps (page 10-268). Second Technician (Operator’s Station) l l l l l l l l l Displace master control panel (page 10-33). Disconnect basket-control panel power harness connector. (CKT 400-459) from master control panel. Disconnect basket-control panel starting harness connector from master control panel. Remove 4   screws, nuts and    washers from master control panel starting harness connector and unmount connector from master control panel. Disconnect control panel power harness connector (CKT 40)) at    HEATER MASTER switch. Set  multimeter to  OHMS .X1 scale   and   “zero” meter,    or use   STE/ICE Test No.    91   (page   4-83). Connect red   probe    of   meter to  c(m{rol panel power harness connector (CKT 400)    al    HEATER MASTER iw]tch. Connect black probe of   meter to   control panel p(wer harness connector D   (CKT 400). Check if   meter indicates continuity. I Does    meter indicate continuity? o^clBCl  Dl_A \ CONTACT D ‘ (CKT    400) \ MASTER SWITCH ./ ( MASTER CONTROL PANEL (REAR VIEW) ) ‘e l l l Replace master contol panel power harness (page 10-101). Install    control panel    starting harness connector in  master control panel. Connect basket-control panel starting harness connector to   master control panel. Connect three battery ground straps (page 10-268). TA107389 4-700