good evening ;

i have this
maxline plus 2 250 GB

code : YAR51HW0
7Y250M00660RB

PCB controller ardent c8-c1


that doesn' spin at all , pcb gets warm when powered "not too hot but remarkebly warm in a few secs of powering up"
drive has no data or importance , and just for pcb diagnostics tests


the 4 motor pins reading 13.70 V when measured .

what r yr ideas ?

thank you very much

Have a donor PCB?

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Hard Disk Drive (HDD), Solid State Drive (SSD, SATA, NVMe, etc), USB Flash Drive and RAID Data Recovery Specialist in Massachusetts

So you just want some experience diagnosing electronic faults?

If so, please upload a detailed photo of your board and I'll help you with voltage test points.

_________________
A backup a day keeps DR away.

thank you for your answers .

no , no donor pcb .

So you just want some experience diagnosing electronic faults?
yes , as this PCB has alots of components to test .

thank you again

I can't see all the component markings, so there may be errors in some of my identifications.

However, I would start by measuring the -5V test point at the negative preamp supply.

Measure the voltages at the pins of VR300 and VR400.

Measure the voltages at the pins of CR201 and Q501.

One of those should be the +3.3V supply for the SDRAM and serial flash memory.

There should also be a Vcore supply for the MCU.

BTW, I would confirm that the +12V supply is not sitting at +13.7 (the voltage that you are measuring at the motor terminals).

_________________
A backup a day keeps DR away.

good morning sir ;


However, I would start by measuring the -5V test point at the negative preamp supply.

-5V is dead ! (reading 0.04 V )

Measure the voltages at the pins of VR300 and VR400.
VR400 : 0 for the big pin-and from left to right pins( 3.27 - 0 - 1.81 )
VR300 : from pin 1 to 8 ( 3.25 - 3.27 - 3.27 - 1.89 - 1.66 - 1.66 - 1.66 - 1.66)

Measure the voltages at the pins of CR201 and Q501.
CR201 : 12 V from one side
Q501 : the big pin 4.48- from left to right ( 3.9 - 4.48 - 3.28 )

the q501 provides the sdram power supply .

motor terminals reading 12.24 V ! strang ! am sure of my previous readings ..


thank you again

Q501 appears to an NPN pass transistor in a +3.3V Vio supply. The output is OK, but the collector voltage of +4.48V looks low. I would have thought that this should be 5.0V, ie the same as the +5V supply. Are you measuring +5.0V at the main power input?

VR400 appears to be a +1.8V LDO regulator. It probably supplies the bridge IC, and/or the MCU.

VR300 looks like the Vcore supply for the MCU. It looks OK, but I'm not completely certain that +1.66V is the correct voltage. Which chip is getting hot, if any?

The -5V supply is controlled by the motor controller. Sometimes even on good boards this supply will be down until the MCU turns it on. I'm assuming that you are testing the board while it is disconnected from the drive. Measure the resistance between the -5V test point and ground. Do this when the board is both on and off the drive. This will test for a shorted preamp.

_________________
A backup a day keeps DR away.

good evening ;

yes , am testing the PCB while disconnected from the media .

testing it while connected , is givving the same result of the -5V supply of the pre amp ,

the pcb getting warm in the area between the motor controller and power devise and the sdram .

testing a new power supply , gave the input value of the q501 a 5.20V reading .

thank you again

ISTM that you may be using an inappropriate power source for your PCB. A switchmode PSU needs a minimum load in order to regulate properly. At light loads, such as a single HDD PCB, the voltages may not be stable. For example, if I use the following PSU (for an external USB enclosure) with a single HDD PCB, then the +12V rail sits at +13.4V and the +5V rail sits at +4.75V. This means that the 12V TVS diode is very close to its breakdown point.

http://azsurplus.com/images/Finecom_XH_34W-12.0-5.0.jpg

Your PC PSU will also be unstable at light loads. Therefore I suggest that you use aluminium clad resistors, or some other arrangement, to provide an appropriate minimum load. In my case I install the resistors inside the PSU, in the fan's air stream, and I fasten them with captive locknuts that have nylon inserts.

Your observation regarding the heating of the PCB is a little unclear. It is quite safe to touch the components with your finger. The area between the motor controller and Q501 and the SDRAM contains small passive devices, so it should not be generating any significant heat. The SDRAM should be reasonably cool, and the motor controller should be warm at most. It will only heat up when driving the motor, if at all. The primary heat source should be Q501. This transistor essentially powers the entire board (except for the +12V stuff). It will probably be dissipating around 1 watt.

Here is a simple diagram of the positive supplies:



The absence of the -5V supply could be due to several things, including the MCU, motor controller, or the -5V supply itself. That's why I asked you to test for a short circuit between the -5V test point and ground, with and without the HDD attached.

Once you have exhausted the simple DC tests, then you will need an oscilloscope to go into more depth. You could also try to communicate with the board in safe mode using your pro tools.

_________________
A backup a day keeps DR away.