WD correct diagnostics

[TaskManager]

Dear all
I have a strange case of WD black edition laptop disk. It has 4 heads in udma head test shows all heads in good condition.
I can copy data using 3 heads ,but when DE comes to one heads it cannot read anything. I tried all options like starting DE / solve slow read etc without success.
I would like to know why only one head behaves like this. If it is weak then how to check .What could be other reasons for this?
can anyone throw light ?

[TaskManager]

Thank You spildit .Case solved 100% Data recovered.

[DR-Kiev]

Head is dead, clone the drive using deepspar by turning off the bad head.
Do a head stack replacement.
Use the deepspar to clone the rest of the data assuming that head replacement was succesfull.

Why you suggest to use Deepspar if Taskmanager mentioned pc3k with DE , which is much better for such tasks ?

Heads replacement is last option to do, don't be hurry with it.
In this case , i am sure, it is no need.

[TaskManager]

Hello all
thanks for all your help.
I did not changed head as client did not approved & was a low budget recovery .Instead I disabled one head and recovered data covered by working heads only. Still I strongly feel Head is not an issue ,but failed to properly diagnose root cause. Disk is stll with me I am ready to try any solution which may lead to study this phenomenon.

[TaskManager]

Maybe BlackST will be able to throw light on this.

[BlackST]

If the drive was not shocked or dropped in any way, it may be only firmware related or head has indeed a physical problem. I'll PM you later with some ideas to try, destructive and non-destructive , just for learning purpose.

[TaskManager]

Thank You Dear

[TaskManager]

Hi BlackST
I have sent pm with sa structure test and screenshots of module check.Actually translator ,adaptive data ,rom image and factory self test modules are corrupt. Has it something to do with this behaviour?
I can mail this results if someone wants to analyse this issue. please give me email id or pm.
thanks a lot.

[TaskManager]

Hello Guys any take on this??