Faulty tubes!

Last night I got out the multimeter and ventured into the blustery car park to test my LED kit. All I can say is gutted!
I disconnected the wires and tested the control box using the circuit test (from the multimeter battery). It was fine. I then tested the tubes wires and found the front and back seemed fine but the sides were dead :(

LED Tubes :(

Well the two side tubes on my undercar LED kit aren't working and haven't been for a while. I emailed litewave who supplied them and got a very useful email back telling me my warranty had expired but giving some advice on finding the fault. Like me, the support guy suspects the control box since two tubes have totally failed (not one suggesting wiring or partially suggesting a faulty LED cluster). To test it he suggested:

1. Remove the wires from the control box.
2. Connect the positive wire for a tube to the positive of a 9v battery and then touch each of the 4 negatives to the battery in turn to see if the LED sections light up.
3. Repeat that for both tubes to see if there is any problem with the wiring or LEDs.
4. If that all works, the control box is faulty but they can replace it for £20
5. Check the wiring and installation for shorts or moisture which might have caused the fault.

This is a big relief as I feared it may be the control box but a new one would require a whole new kit! I will grab a couple of 9v batteries from the shop near work and try this out tonight. If it is confirmed to be the control box, I'll order a new one tonight and probably an extra tube to go above the mesh in the bumper :)