Fails when executing job called syspolicy_purge_history (SQL Server 2012)

Question

Hi friends i have the following  problem
The job syspolicy_purge_history  of my database engine failed, specifically on the third step called "Erase Phantom System Health Records" that executes a powershell.  This is the sentence that executes (All job syspolicy_purge_history
on any SQL 2012 has the same code):
if ('$(ESCAPE_SQUOTE(INST))' -eq 'MSSQLSERVER') {$a = '\DEFAULT'} ELSE {$a = ''};
(Get-Item SQLSERVER:\SQLPolicy\$(ESCAPE_NONE(SRVR))$a).EraseSystemHealthPhantomRecords()
.  When i see the job history i get the following:
Message
Executed as user: NT Service\SQLSERVERAGENT. The job script encountered the following errors. These errors did not stop the script:  A job step received an error at line 1 in a PowerShell script. The corresponding line is 'import-module SQLPS  -DisableNameChecking'.
Correct the script and reschedule the job. The error information returned by PowerShell is: 'The specified module 'SQLPS' was not loaded because no valid module file was found in any module directory.  '  A job step received an error at line 2 in
a PowerShell script. The corresponding line is '(Get-Item SQLSERVER:\SQLPolicy\SRV01236$a).EraseSystemHealthPhantomRecords()'. Correct the script and reschedule the job. The error information returned by PowerShell is: 'Cannot find drive. A drive with the
name 'SQLSERVER' does not exist.  '  A job step received an error at line 2 in a PowerShell script. The corresponding line is '(Get-Item SQLSERVER:\SQLPolicy\SRV01236$a).EraseSystemHealthPhantomRecords()'. Correct the script and reschedule the job.
The error information returned by PowerShell is: 'You cannot call a method on a null-valued expression.  '.  Process Exit Code -1.  The step failed.
Aditionally i tested putting the policies in powershell like unrestricted (like i see on a blog). but it didn't work.
My SQL version is 2012 Standard SP1 X64
Please help me with this
Thanks for your help
Greetings
Aleds

Answer 1

Thanks for your help princekumar8 and gona_david
Hello Gona_david,  You are right, when i execute the powershell sentence Get-Module -ListAvailable
the SQLPS module doesn't appear. 
Look i have another SQL Server 2012 in another server, but this is patched on SP2 and the syspolicy_purge_history here runs OK.  Also when i execute the powershell, the SQLPS appears in the list.
So, my question is: If i patch my server SQL Server 2012 with the error from SP1 to SP2, is Possible that the error will get away? In fact, Wouldn't be yet necessary runs the SQL install? 
Basically what you recommend me in this case?
Thanks in advance 
Greetings 
Aleds