Repairing a dead Nortel/Avaya 1100 Series IP Phone

Nortel 1165

Nortel 1165

At work we use Nortel/Avaya BCM voice over IP telephone systems with an 1100 series IP phone on each user’s desk. We’ve had the system for about 3 years now and have had little to no problems with the phones. Just recently we’ve had to replace several phones due to unknown issues preventing them from powering on or booting. A new phone costs around $500, so after replacing a few I was looking for another solution as we don’t have a warranty or maintenance agreement on them. I suspected a power issue and decided to investigate there first.  Sure enough there were capacitors on every one of the broken phones that were busted or about to bust.

Here is my tutorial on how to fix a phone for about $0.25 each. You’ll need some soldering skills, a soldering iron with a small tip, rosin core solder, desoldering braid, 2 100µf 25V capacitors, 2 470µf 10V capacitors, and about 20 minutes of time per phone. The capacitors I initially used came from Radio Shack, but they are a little expensive and the voltage doesn’t match the originals. The voltage not matching is OK, but it makes them a little large for the spaces provided on the circuit board. I recommend going to Jameco and ordering the ones you need from there. Enough capacitors for me to completely replace the ones that go bad on 50 phones cost me $11 not including shipping. The part numbers I used for ordering were 93761 for the 100µf and 1946279 for the 470µf. Let’s get started!

Capacitors To Be Replaced

470µf are at the top, 100µf are at the bottom

Start by cracking open the phone. There are 7 screws on the back that you remove to open up the casing. You’ll need to reposition the base on the phone to get to all of them. I recommend a skinny phillips screwdriver to get to all of them. Once you open the back of the phone you’ll see a green circuit board with a yellow-ish white one stacked on top of it. This top board is the one you’re after. Use a small flat-head screwdriver to gently pry up the board using the phone casing as a pivot point. Be careful NOT to use other things soldered to the board as a pivot point. You may damage something that can’t be repaired. The picture shows the capacitors that are most likely bad. I’ve repaired phones that only needed one replaced, but sometimes all of them are bad. I think it’s a good practice to just replace them all while things are disassembled. Signs to look for are a bulging top (vent) or a bulging bottom (look at the board from the side). You might also notice a burnt electronic smell or see brown goop on the circuit board around the capacitors.

The power board has a flat side with 2 solder points on the back. You’ll need to use the desoldering braid to remove the solder and free the wires connected to them. Bend them up to free them from the board. Next you’ll have to cut a piece of tape holding the 2 pieces together and find the area where some white thermal paste is holding them together. Use a small flat-head screwdriver to gently pry the 2 pieces apart.

Capacitor solder points

Capacitor solder points

Next is the tricky part. Locate the opposite side where the capacitors are soldered to the board. You can mark them with a permanent marker if it helps. place the soldering braid between the iron and the areas you want to remove the solder from to free the capacitors from the board. Make a note of which go where or simply work one at a time. Capacitors have a positive and negative side just like a battery. You’ll notice a stripe on each side noting which wire is which. It’s important to get the polarity correct. If you inspect the area where the capacitor is going, the negative side goes in the hole next to the thick black bubble. Insert both electrodes, flip the board over and apply a little solder to each one. Clip off the excess wire as close to the circuit board as you can. Repeat for all the capacitors. Work in reverse reassembling everything. Put the 2 pieces of the power board back together and re-solder the pins on the back. Slap the power board back on the phone, and give it a test before putting the case back on. If everything has been done correctly, the phone should power on, boot, and you will have saved enough money to make your boss happy. Warranty? Who needs a warranty!

This does leave me wondering about a quality control issue wherever these phones are manufactured. Like I said earlier, we’ve had the phones for over 3 years now and never had any problems, but in the last week I’ve fixed 6 phones.

UPDATE – July 2011: Avaya has issued a Product Correction Notice detailing what to do if you are experiencing this issue. Please check here:
Special thanks to Hugh O’Neill who posted this link it the comments section.

UPDATE – August 2011: After a conversation with a local Avaya rep, I have been told that the part number mentioned in the PCN posted above is for use by Avaya for installs by Avaya techs only. If you are going to replace the modules yourself, you need a different part number and must recieve authorization from Avaya to order it. The part you must order is NTYS17PMPP. This part number is for a box containing 96 power modules. You can only order by the box. You cannot order individual power modules. I was also given a link to download instructions on disassembling the phone and replacing the module. This .zip file can be found at: