Original Xbox
Service 12 DVD Repair
September 28, 2022
The latest Xbox to hit the bench was reported to have issues with the DVD drive. Sure enough when powering up I saw red and orange flashing LEDs, and a Service 12 message appeared on the screen. So it would seem reports of a DVD issue were accurate.
Opening the console I looked for the usual suspects including loose or incorrect cabling. The IDE cable in the back of the drive was not fully inserted. After fixing this I powered the system up, hoping the problem would be solved but unfortunately it was not to be. Next I looked for bulging capacitors, but everything looked ok and there was no signs of leakage. The next step was to swap out the IDE cable with a known good cable. When this didn't solve the problem I also swapped in a known good power cable but the system was still in error.
I found another 1.6 system, and amazingly it had the same model of DVD drive as the failed one. After subbing the new drive in with the original cables I confirmed that the console worked properly. So definitely something in the drive was causing the problem.
It was time to open the bad drive and review the PCB. There were no obvious signs of damage, no bulging capacitors or loose cabling. I took the PCB from the good drive and installed it in the bad drive. The system booted without any issues. So the problem was on the PCB but there were no clues as to where.
I started testing various components, capacitors, resistors and diodes to see if I could find the issue but I wasn't making any ground. Then it hit me, there is a technique I've seen used in electronics repair where diode mode of a multimeter is used to read the voltage drop to ground at various points on a board, but it requires that a known good board is available for comparison measurements. It seemed like a great path forward from where I was.
With the red lead on a ground point I began taking diode measurements from all of the connectors on the good board. I then began reading all of the points from the bad board and recording the results. Once finished I was lucky enough to have only one point which was notably different between the boards.
Pin 19 on the IDE controller was OL on the bad board. Inspecting the pin I could seen a trace leading to a resistor network as the first stop. I measured across the resistor and it was open. I was able to solder a replacement 33ohm resistor in line with the pin and jump the open resistor. After the repair was done I confirmed that the diode reading was now in line with the good board and I reassembled the bad drive.
When I next powered up the console it booted perfectly. I was able to load several DVDs into the drive and they all read without any issues. Admittedly the jumper wire is a little long, but I was happy to have identified the issue and work around it.
It seems like comparing diode readings between a defective and good board can provide a way forward when there is little else to go on. Here are a few reference readings which someone might find helpful if you have stumbled across this page.
