adidas original backpack Keyboard not working at boot
Dell Dimension 2400. Error message 8602.
Auxilliary device failure. Keyboard controller failure. Message says strike F1to continue, F2 to run setup utility.
I cannot do anything because the keyboard does not respond. Tried three different keyboards PS/2 keyboards but have not tried USB keyboard. All cable connections to motherboard firm.
Tried booting into DOS using floppy and Linux on DVD but always get the same message. Disconncted everything except keyboard.
Just been looking on a Dell forum and someone has written that if replacing keyboard does not help motherboard needs replacing.
Any suggestions please? Thanks in advance.
You may not have to replace the mobo. It may simply depend how handy you, a friend, or a repair center is.
The PS/2 port often still uses an actual one time fuse for the +5V output (needed to power the keyboard). In other words, you overload the connector one time, and it’s kaput until the fuse is replaced.
Other motherboards use an auto resetting “fuse” (phase change technology) but the problem remains that if it is overloaded, it will not provide power to the keyboard. Even if the problem is corrected, it can take a few minutes for the phase change device to cool down enough to reset itself. So, you may not be able to immediately fix the problem, re power up and expect it to work. You may have to wait a minute or two.
The upper limit can vary from mobo to mobo, and some of the new keyboards take a lot of power, perhaps more than some mobos can provide before the fuse kicks out. (as an aside, the USB device standard limits USB devices to pulling a maximum of 500mA from the USB port)
An PS/2 port overload can be caused by a transient, or even mis alignment while plugging/unplugging the keyboard while power is on (not good to do with PS/2 connection for other reasons, too)If you can detect +5V at the PS/2 port pin4, then a “blown” fuse is not your problem. In some cases, an external device may indicate the presence of +5V by lighting an LED(s) even if the device itself is non functional. Otherwise, you can just measure pin4 for +5V using a volt meter. If you do not verify the presence of +5V at pin4, then it’s time to check the fuse itself.
If you can locate the fuse (on the mobo), it’s easy to test with an ohm meter or continuity tester. The fuse is usually the last component in line between pin4 (+5V) of the PS/2 port and the rest of the mobo circuitry.
You may be able to easily replace it. You can order small PC board fuses from electronic supply shops. In some cases, a suitably sized “wire link” fuse constructed from a single strand from a small gauge stranded wire may suffice. Even a larger single 32ga. wire wrap wire may do in a pinch. Whatever you do, make sure it will “blow” at an appropriately safe current level.
Rather than remove the old fuse and try to solder in a new fuse, I have sometimes just soldered the new fuse on top of the old one.