Master Control Panel 5000

28th January 2016

If the unit functions erratically or the battery life is short the first thing to check is the voltage across 12R149 (100k). 10 seconds after pressing a key the voltage should be zero, if it isn’t the panel won’t switch off properly. Should a voltage be present, the most likely cause is leakage in the keyboard, this can be localised by checking the voltages across R102 > R118 (10k, even numbers only). Readings other than zero at any of these points show which column the leakage is in. Carefully removing the protective film and the contact plates should allow sufficient access for the area to be cleaned to remove the fault. [Master Control Panel 5000]