3195743 - Unable to open transformation in modelling tool.

When trying to open transformation in modelling tool, it is failing with below error,

System failure: "Invalid access to a string (too long)"

or 

dump in the backend:

Category               ABAP programming error
Runtime Errors         STRING_LENGTH_TOO_LARGE
Except.                CX_SY_RANGE_OUT_OF_BOUNDS
ABAP Program           CL_RSDHA_AMDP=================CP
Application Component  BW4-DM-TRFN

 "STRING_LENGTH_TOO_LARGE" CX_SY_RANGE_OUT_OF_BOUNDS                                           |
|    "CL_RSDHA_AMDP=================CP" bzw. CL_RSDHA_AMDP=================CM01A                   |
|    "P_ADD_PROCEDURE_ABAP_EXPERT"

|  205|                                                                                            |
|>>>>>|    IF l_tmp_source IS NOT INITIAL AND l_tmp_source(7) = |{ p_c_abap_header } |.            |
|  207|      " Existing codin

• SAP BW/4HANA 1.0
• SAP BW/4HANA 2.0

STRING_LENGTH_TOO_LARGE,CX_SY_RANGE_OUT_OF_BOUNDS,Invalid access to a string (too long). , KBA , BW4-ME-TRFN , Transformation Metadata , Problem