Step 6: Multimeter testing

Measure the resistance of your stitching.
Switch the setting of your multimeter so that it measures resistance. Measure resistance from the + of the power supply to the + of the LilyPad, and the - of the power supply to the - of the LilyPad. If either of these resistances is greater than 10 ohms, reinforce your stitching.

There are two ways to reinforce your stitching. If the resistance is barely above 10 ohms, you can reinforce using more conductive thread. However, if the resistance is extremely higher (greater than 50 ohms), you can reinforce using conductive fabric, which has much lower resistance than thread. In order to do this, cut a strip of conductive fabric and iron it onto the back side of your garment such that both ends of the strip are touching your stitch path. Then, make several stitches from the conductive thread of your original path, and stitch onto the conductive fabric (so that the stitches you're making are on top of the conductive fabric (see photo below)) so that the thread and the fabric are connected. Repeat for the other end of the strip. This should greatly reduce your resistance.

Also check resistance between the + and - stitch paths. If the resistance is less than ~10k ohms, you likely have a short. This may be because a fine hair from one path is touching the other path. Trim the hair, and you should be okay.

Test your stitching.
Once you're certain that you have no shorts, put the battery into the power supply and flip the switch on the power supply to the on position. The red light on the power supply should turn on. If there is no red light, turn off the switch quickly and see whether there is a short between your + and - stitches.

If the red light is on, press the switch button on the LilyPad main board. The light on the LilyPad should blink each time you press the switch. If it doesn't, the resistance between your power supply and LilyPad is too high, and you should reinforce your stitching.