193111-050 
MAINTENANCE 
Troubleshooting 
 
  
  
 DANGER: ELECTRICAL SHOCK HAZARD — Before checking electrical components,  
 turn OFF and remove fuses of disconnect switch (supplying AC power to charger),  
 disconnect battery, and check for voltage on capacitors. Discharge through insulated 
 screwdriver if there is any reading. 
 
 
 CAUTION: HIGH VOLTAGE FROM TEST EQUIPMENT can damage silicon diodes and other  
 parts. Short silicon diodes with extremely short leads, or disconnect, before applying voltage  
 from a "megger" or other high voltage test equipment.  
 
 The following chart contains information which can be used to diagnose and correct unsatisfactory operation  
 or failure of various components of the unit. Each malfunction is followed by a suggested checking or inspection 
 procedure. Refer to Connection/Schematic Diagram in the Diagrams chapter included in this manual. 
 
Troubleshooting Guide 
 
 No charging current (Ammeter reads zero) 
 
 Check line voltage. 
 
 Close fused disconnect switch or repair open circuit. 
 
 Check for proper line voltage. 
 
 Refer to Line Voltage Changeover instructions in Installation chapter. 
 
 Check for blown fuses. 
 
 Replace blown fuses. See Table 4-1 for proper fuse sizes. 
 
 Check for internal short circuit (diode, winding, wiring). 
 
 Repair short circuit, or replace faulty component. 
 
 Check for "open" battery circuit. 
 
 Clean and tighten connections, especially battery cable connections. 
 
 Check Charge Control. 
   
 Connect a jumper from the red-white lead of Control Transformer T1 to the red  
 lead of Contactor K1 coil. If charger starts and ammeter shows charging current  
 when a battery is connected, check further for faulty printed circuit card on control 
 and replace as necessary. 
 
 Check output circuit fuses. If fuse has blown, check for problem causing fuse to blow. 
 
 a.  Reverse battery connections, if polarity is wrong. 
 
 b.  Determine whether a diode is shorted. Refer to Silicon Diode Testing in Maintenance 
  chapter. 
 
 Low charging current at beginning of cycle (battery fully discharged) 
 
 Check for failed capacitor (s) (one or more). 
 
November 17, 2020                    6-3