Note: Will also cause light films 1) Recalibrate CAL GENERATOR portion only if the exposure time is longer than 2 ms and the kVp is less than or equal to 75% of selected kVp 2) Check that K7 Safety Contactor on AMX1 A4 panel closes (Contacts welded/loose Leads/Bad coil) Verify proper Microswitch (Aux) closure (K7 Safety Contactor is orderable Part # 46-262695P5). A faulty K7 Safety Contactor, might not give any errors—but you will not be able to CAL BATT CHARGER portion in the Calibration mode. As a rule, if the unit was manufactured prior to June 1994, REPLACE the Safety Contactor assembly (order part # 46-262695P5) 3) Filament kVp Board may be defective 4) 1 KHz Inverter Board may be defective 5) Loose connectors on Filament kVp Board or 1 KHz Inverter Board 6) Stop/Start Power Module SCR 800V 200A, Q3 on AMX1 A4 panel may be defective 7) If EXP START Is shaky or Hi all the time (it should be a pulse), troubleshoot the EXP START CMND circuit on the 1 KHz Inverter Board 8) Verify that the tap relays contacts are coming in firmly. No external interference (Check fish-paper is not loose/curled on inside side panel cover, replace fish-paper with 3M mylar insulator orderable part # 46-315281P1 or 2801253) 9) Loose leads on service toggle switch (not going to applications) 10) Defective CPU Board 11) Defective Rotor Control Board 12) Bad High Voltage Tank Transformer 13) Loose Anode or Cathode High Voltage Cable-spread pins at both ends of Anode and Cathode HV Cables 14) P1/P2 leads exhibit leakage to ground 15) 439 and 462 Errors together indicate battery/cell problems 16) 439 and 43E Errors - replace Filament kVp Board and/or 1 KHz Inverter Driver Boards - check filament High Voltage cables 17) AMX1 A4 C5 leaky to ground 18) Refer to item 19 in 469 Error listing 19) AMX1 A4 C6 bad (Filament kVp Board J8 Pins 1 & 2) 20) Check for weak (“soft”) batteries/cells. 21) Bad main Power Module SCR(s) Q1 Or Q2 blocks 22) Bad AMX1 A4 R7 (Auto-Transformer) 23) Bad tap relay(s) – Check the K6 tap relay for good normally closed contacts