Apple iPod HI-FI Dock A1121 (M9867ZH/A)
If you are here, you probably know what the Apple iPod HIFI Dock / Speaker is: the single rare and discontinued Apple speakers dock, which still presents high interest for the enthusiasts.
Identification
- Part No: M9867ZH/A
- Model No: A1121
Apple iPod HI-FI Dock Internal Design
How to Open Apple iPod HI-FI Dock
Before reaching to any screw on this product, you have to unglue the front black aluminium panel (the one you see after taking the grill off). A layer of glue is used on the whole surface of this 1-2mm thick aluminium panel, which makes this product one of the worst repairable.
Taking this step should be done with high caution as it can lead to damaged speakers or bent front plate. The easiest method I found is to preheat the front plate gradually with a hair-dryer, as you advance with a cutter between the front aluminium plate and the underside baffle, putting constant tension on the aluminium plate to help prying the glue. This is a two persons recomended job, as you have to hold the heater, apply tension to the plate and pry with a cutter or knife at the same time, all in a good lighted environment. Pay very close attention to where your cutter blade reaches, as there is a very high chance to get it into the exposed speakers rubber surround suspension !!!
Inside the Apple iPod HI-FI Dock
Apple iPod HI-FI Dock Troubleshooting Service Instructions
Apple iPod HI-FI Dock Power Supply
Power supply is Lite-On PA-3150-01A and provides a total combined DC output of 30W.
The power supply assembly is providing required voltages for the amplifier and charging docking board, but also signalling low battery and good battery when running on batteries.
Apple iPod HI-FI Dock Power Supply Components and Repair Tips
Stay tuned for more photos !
Leaking capacitors – common main fault of Apple iPod HI-FI Dock failure
The big 450v/100 uF capacitors used inside the power supply are manufactured by TAICON. TAICON brand is the short name for Taiwan Capacitor Ltd, which was established in 1969 in Taipei, Taiwan by Nichicon Japan, as a joint venture, for production of aluminum electrolytic capacitor. The relation with Nichicon sounds like a good thing, but there is a big amount of reports of failed Taicon capacitors in brand computers like Dell, and various motherbards. for production of aluminum electrolytic capacitor. Word is that Taicon was also behind the defective Nichicon HN and HM series.
In my conclusion, they should be considered the low-cost Nichicon, but definitely no warranty of sustained quality or high quality expectations, especially when used in high temperature conditions (like the closed, no cooling enclosure of the iPod HI-FI dock PSU).
Proof of the low quality of these capacitors is that in most cases on this device, they leaked from bottom, instead of venting on the top. This also causes corrosion to the printed circuit board, and helps bonding carbon connections between close spots under them. There is one spot on this PCB where you have to thoroughly clean the board, because the copper of the positive and negative are close enough to short-circuit when aided by this fault.
Symptomps of leaked capacitors on the iPod HIFI dock:
- no power at all (burned/melted thermal fuse and/or thermistor)
- not running on batteries either, as reported by other cases
Other effects of leaked capacitors:
- pcb contamination
- rotted cable cushion/damping foam
- contamination of other components as an effect of the blowing fuse
Power Supply Thermistor
Inline with the input power cord is a NTC power thermistor, part number SCK10-2R55A. It has 2.5 ohm resistance at 25’C and can handle a 5A current. It’s main role is to aid gradual charging of the four big capacitors. SCK10-2R55A Datasheet
Power Supply Bridge Rectifier
Bridge rectifier is KBP-206, which can handle 2A.
Apple iPod HI-FI Dock Power Supply Connectors Pinout
Pin Nr. | Wire colour | Signal | Value range |
---|---|---|---|
Gray | Amplifier voltage | + 17V — 1.6A (0.5A on DC input) | |
+3.3V — 0.1A | |||
+6V — 0.3A | |||
Violet | Low Battery | ||
Brown | Battery Good | ||
Black | Ground | ||
Black/White | RTN | ||
Black | DC INPUT BATT+ | 7.5~9.9V — 5A | |
Black | DC INPUT BATT- |
Apple iPod HI-FI Dock charging iPod circuit mods/enhancements
The charging specification is 12V FireWire charging, unlike the 5V USB specified in 2008, so newer devices like the iPhone/iPod nano 4th/iPod touch 2nd can not be charged.
Solutions to these issue can be found here: