Can't find hard drive

MBP 13" late 2009

replaced with new hard drive

after about 6 months the HD is not recognized

I'll pulled the drive, placed it in a dock

the HD is recognized and mounts

plugged HD back into the MBP but is not recognized

I done this with 2 drives

they both mount on my iMac

placed both drives in the dock

they mount

I optimize one of the drives and do a clean OS 10.10.3 install

I run Tech Tools pro - reports no problems

I run disk utility - no problems

I run Disk Warrior - no problems

I replace the HD in the MBP - the drive is not recognized

I've done command - R but can't access it

Option - D can't access this

Zapped P-RAM

Help.

John