LiftMaster LA400DC LA400DC Owner's Manual - Page 42

TROUBLESHOOTING TROUBLESHOOTING CHART continued... SYMPTOM Maglock not working correctly. POSSIBLE CAUSES a) Maglock wired incorrectly Solenoid lock not working a) Solenoid wired incorrectly correctly. Switched (SW) Accessory power remaining on. a) In limit setup mode Accessories connected to a) Normal behavior Switch (SW) Accessory power not working correctly, turning off, or resetting. Accessories connected to Accessory power not working correctly, turning off, or resetting. a) Accessory power protector active b) Defective control board Quick Close not working correctly. a) Quick Close setting incorrect b) Interrupt loop detector c) Defective Expansion board Anti-Tailgating not working correctly. a) Anti-Tail setting incorrect b) Interrupt loop detector c) Defective Expansion board AUX Relay not working correctly. a) AUX Relay setting incorrect b) AUX Relay wiring incorrect c) Defective Expansion board SOLUTIONS a) Check that Maglock is wired to N.C. and COM terminals. Check that Maglock has power (do not power maglock from control board accessory power terminals). If shorting lock's NO and COM wires does not activate Maglock, then replace Maglock or Maglock wiring (refer to Wiring Diagrams). a) Check that Solenoid is wired to N.O. and COM terminals. Check that Solenoid has power (do not power solenoid from control board accessory power terminals). If shorting lock's NC and COM wires does not activate Solenoid, then replace Solenoid lock or Solenoid wiring (refer to Wiring Diagrams). a) Learn the limits a) Move accessory to accessory power "ON" a) Disconnect all accessory powered devices and measure accessory power voltage (should be 23 - 30 Vdc). If voltage is correct, connect accessories one at a time, measuring accessory voltage after every new connection. b) Replace defective control board a) Check that Quick Close setting is ON b) Check operation of Interrupt Loop detector c) Replace defective Expansion board a) Check that Anti-Tail setting is ON b) Check operation of Interrupt Loop detector c) Replace defective Expansion board a) Check AUX Relay switches settings b) Check that wiring is connected to either N.O. and COM or to N.C. and COM. c) Set AUX Relay to another setting and test. Replace defective expansion board. 40