No Lights: The battery may be dead – test and replace. Make sure its installed + side up. Switch may not work right – push down to flex it or add tape to the underside of the switch. Be sure the blue wires are connected to the top strip in the back and the red wires to the bottom strip. A short is another common cause. Check to see that there are no bits of tape or wire causing a short. Make sure the third tape is not touching the bottom of the battery (see assembly step 3) and that the battery is tight to the board.

Lights Always On: For sure, the switch is not working correctly. Check that no copper is bridging the gap on the front of the board (assembly step 2) and that there are no pieces of copper foil bridging the gap around the rivet hole on the switch.

Switch only works when pushing down on it: The board may be warped causing the switch to not lie flat and properly bridge the gap. Loosen the screws and push the board flat. Flex the switch so it presses down harder against the tape on the board. Screw the board down evenly with the lights on. If the lights go off, loosen that screw and tighten another until they are all snug and the lights are on.

Only 1-3 Lights on: Poor connection between copper tape and twisted wires on back of board. Press down harder on the tape around the wires or gently remove, re-twist the wires tighter and re-tape.

Flickering Lights: Probably caused by a bad switch (see above) or the third tape not holding the battery down tightly (adjust). Can be a poor connection between the twisted wires and copper foil on back of board. Press and smooth tape and/or remove and twist tighter.

Damaged Rivet: If the rivet is damaged or does not hold the switch tight to the circuit board remove it and use the spare screw in its place to hold the switch down securely.

Tape Doesn't Hold Wires Down: If the tape does not stick to board or to the other copper tape it is likely that finger oil residue on the surface is preventing it from sticking. Clean the surface with rubbing alcohol (isopropanol - Caution: Adult supervision) and the tape should hold.

Broken Wire: Occasionally the stripped end of a wire may break off during twisting. You can fix this with a pair of fingernail clippers and very, very carefully cutting into the insulation while pulling on the wire. Rotate it slowly as you work and you should be able to strip the insulation from the wire.

Replacing Battery: The battery will give 20-30 hours of light which is way more than enough for a Derby race. To replace the battery, carefully cut along the side of the tape and peel it back from the battery. Place the new battery + side up in the circle and put the tape back over the battery. Use part of the leftover copper tape to repair the cut or wrap electrical tape over the copper tape to hold the battery down. There needs to be a copper path for the electricity to flow from the + side of the battery to the red wires on the back of the board.