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How do you perform a continuity test?

If all the lamps flashed on and then off, it’s likely the ballast. If one or two of the lamps flashed on, it’s likely something wrong with the wiring or lamps. If you have swapped ballasts and the lamp light up, you know there is a problem with the ballast.
If your dealing with a Vue430 model ballast and a certain bulb doesn’t light is where to begin investigating. If all the lights flash on and then off it’s likely the ballast. Check the continuity using the procedure below if possible before sending it in for repairs to make certain it is the ballast at fault.
A Vue660/430 ballast will not work for a moment, before it shuts down. Unlike a conventional ballasts, these ballasts will not continue trying to run if it detects an open circuit. In this case, the problem could be a broken bulb filament or the bulb may not be making contact with an endcap’s pins.
For those with an OHM meter or continuity checker there’s a quick test that can be performed to troubleshoot our fluorescent ballasts. This is for situations when some of the lamps flash on and off for a split second while other lamps do nothing. The lamps that flash are fine and you need to check the other connections. You will need to power the ballast off and on again to check to see if it will work. Fixing the problem without powering off the unit will not cause the lamps to light. Repeat on and off cycles quickly will cause a ballast failure, so please don’t go crazy. Please submit a help desk ticket stating your issue. If you have another ballast of the same model, always try switching ballasts out to see if the problem is associated with the ballast. Otherwise, read on for instructions to the continuity test.
  1. Unplug the unit from the power source.
  2. Pull the wire harness (connector) off the ballast. The test does not require any AC electricity.
  3. With the endcaps MOUNTED and lamps securely in place, you can now begin to test the entire system from the end of the harness (the male Molex connector, the part usually inside the ballast).
  4. Use the two probes as follows:
For each pair of colored wires used in your application you want to test for continuity. To do this you insert the probes into the exposed Molex pins that are connected to the correct wires. Wires not used, like for a Model 660 using 2 or 3 lamps are ignored (these wires should be individually CAPPED OFF for possible use in the future).
  5. If you find you have continuity (the signal from one blue wire, for example, goes down the wire, to the endcap, to the lamp’s pin, across the filament, back to the pin, the endcap and to the blue wire and back to the connector) check the other pairs. If they all have continuity, the only other connections are the jumper wires. Check those lamps at that end by going pin to pin on the same end of the lamp.
  6. If it shows continuity on all connections, your ballast needs to be sent in for a fast service. You will always get a small resistance reading through the circuit. A reading of 10 ohms or less is satisfactory. If there is a problem in one of the lines it will be obvious. You will see a drastic difference in readings. For example all your lines read less than 10 ohms except for one which reads completely open (infinite) or in the K-ohm range. *Send the ballast only and a note inside with your name, address, email, reported problem and daytime phone number we can reach you at. Turnaround is 3-4 business days or less.