Repairing a Bose SoundDock iPod Speaker

I went to Goodwill a few days ago and left with a $20 Bose SoundDock for my 4th Gen monochrome iPod. Once I got it home I plugged everything in but the dock wouldn't power on. A multimeter confirmed that the power supply wasn't outputting any voltage (note that I didn't know the pinout and tested every combination).

You'll need the following items to follow along:

• 100uf 25v capacitor
• Philips screwdriver
• Flathead screwdriver
• Soldering Iron
• Solder
• Pliers
• Wire Cutter
• Exacto Blade
• Metal spudger (optional)
• iPod

Some online sleuthing brought me to Circuit Diagram for Phihong PSM36W-201 Power Supply on the Klipsch forum. Apparently this was a common power supply back in the day for audio devices. I ordered some 100uf 25v capacitors from the internet hoping that it would solve the problem and they arrived a few days later.

Power supplies like this are a nightmare to open. They're basically designed to be thrown away once faulty. I scored the seam with an Exacto blade for a half hour and then took a flat head screw driver to it, stabbing in the center of the long sides and rotating. The goal is to crack the power supply apart without damaging the internals and saving enough of the plastic shell that it can be duct taped back together.

Once the case is removed the innards consist of a circuit board and a heatsink. The two need to be separated so that the capacitor can be desoldered and replaced. There are three philips screws that need to be removed. The difficult part is that there are three transistors clipped to the heatsink and a thermometer glued to the heatsink.

I used a metal spudger for repairing iPods to remove the clips by first inserting them near the top between the clip and the heatsink then sliding it down to where they were tightly connected, then pushing it all back up until the clip pops off. There was also some Kapton tape behind the transistors that I had to peal as well.

For the thermometer I used the Exacto blade to cut the glue and separate it from the heatsink. You'll need to be careful to not bend it too far since it's in there pretty weak.

Part of the aluminum heatsink was cut in a way so that it sort of held onto the circuit board. I had to bend it with a pair of pliers. Once that was done I was able to slide the circuit board from the heatsink.

Once the circuit board has been removed look for the capacitor labeled 100uf 25v. It's the small one next to the giant one. In my case it looked completely normal. You'll also need to note which side is negative. To remove it I used a pair of wire cutters to cut the ledes, then I hold onto the leads with the pliers with slight pressure, and heated the lede and solder with a soldering iron so that the ledes would pop out.

After that I stuck in the new capacitor, making sure that I aligned the negative lede with the hole where the old capacitor's negative lede went. Heat the lede, hold solder to it, melt it together, and cut the excess lede, rinse and repeat.

Once the new capacitor is in it's time to test it. Make sure the bottom of the circuit board isn't touching anything conductive, like metal or your finger. Plug the power into the wall, then either test the port with a multimeter or plug it into the SoundDock and play something with your iPod. In my case I immediately got a reading of about 17.5v.

Now you need to reassemble the heatsink and the circuit board. Slide it back together and put the screws back in. The clips are annoying to put in; I was able to make a ramp using the spudger against the stepped surface of the transistor then slide the clips over it.

The thermometer is harder since the glue has been cut and it's not making a good connection to the heatsink. In theory the power supply uses the thermometer to cut power when it overheats, which means a bad connection could mean an overheated power supply. I used some CPU heatsink compound and some junk metal materials to form a new clip and hold it together. Good luck.

Stick everything back into the case the best you can. It's important to get the power plugs lined up properly since you don't want to trip on a cord and make things worse. Push the case together and power the dock again to make sure it still works since wires can shift around. Once satisfied either wrap it in tape or super glue it together.

Thomas Hunter II is a staff Software Engineer with 18+ years building scalable, production-grade systems. Deep expertise in Node.js, observability, and developer tooling, with a strong track record of driving architectural decisions, mentoring engineers, and improving customer facing technical documentation. Author of 5 books (including O'Reilly), certified by the OpenJS Foundation, and frequent international conference speaker. Passionate about delivering reliable, maintainable software at scale.