How to Fix an Electric Heating Pad

My theratherm® electric heating pad quit working. Dashes would show up on the screen instead of the temperate when you plugged it in and heat wouldn’t be produced. If you twisted the pad the right way though, the temperature reading would show up and it would start heating.

By twisting the heating pad while it was turned on I knew that the issue was in the pad itself and not in the electronic control. I was hesitant at first to try to repair it because I guessed that I wouldn’t be able to find (or fix) the problem. There are wires running everywhere through this professional heating pad.

I was going to throw it away but I didn’t feel right about it. I’m frugal repair, right? Plus, this is my favorite heating pad (great temperature control, moist heat, ,etc). So I decided to try to figure out the problem and get it working again.

The first step was using trial and error to find the spot where the break in the wire was (that was my assumption). You can see the marks above, I first found the area where the heating pad would turn off and when twisted properly, it would turn on again. After a little more precision twisting I was able to find the spot where the problem lie.

After cutting through the edge of the fabric I could see a black wire that looked like it had some spots that were pinched. The pink heating cable looked OK to me.

I carefully cut the sheathing off the black wire where the kink was that was causing the problem. This revealed four more wires! I separated those four and used trial and error again to figure out which wire was the problem one. Not only could I detect that the orange wire was broken, I could physically feel the break in the wire. Culprit found!

Next, I cut the wire at that location, stripped the wires on both sides, slid some heat shrink tubing on the one side and then soldered the wires back together again. Then I pulled the heat shrink tubing over the new solder joint and heated it up with my hot air station to get that nice snug insulation.

I immediately plugged the heating pad back in and saw that it was working! I twisted the pad all over to see if perhaps there was another break in a wire but I wasn’t able to find one. This little orange wire inside the black wire had a small break in it that was causing this theratherm® heating pad not to warm up.

I then wrapped the four wires in electrical tape and handed the heating pad to my wife who graciously agreed to sew the seam back together for me.

This repair took about 30 minutes to do. One of the keys to this repair was my willingness to try it. I have not repaired a heating pad before and I wasn’t sure I would be able to do it, or that it would be worth the time. But one thing I have learned over many years of repairs is that fear is usually the biggest obstacle and causes people (me included) not to try.

The other big factor to the speed and success of the repair was having good repair tools on hand. Having wire strippers, shrink wrap tubing, and especially my solder iron easily available made this go so much faster and easier. If you want to see the tools I use, check out the Recommend Tools tab at the top.

Happy Fixing!