• Idempotent Rising-0 coupling fault 
between cell i and j : (i) Cell j is to be written with a 0 and read back, (ii) cell i is to be written with 1 and read back, (iii) cell j is to be written with a 1 and read back, and (iv) value at cell i is to be read and checked to be 1.
• Idempotent Rising-1 coupling fault 
between cell i and j : (i) Cell j is to be written with a 0 and read back, (ii) cell i is to be written with 0 and read back, (iii) cell j is to be written with a 1 and read back, and (iv) value at cell i is to be read and checked to be 0.
• Idempotent Falling-0 coupling fault 
between cell i and j: (i) Cell j is to be written with a 1 and read back, (ii) cell i is to be written with 1 and read back, (iii) cell j is to be written with a 0 and read back, and (iv) value at cell i is to be read and checked to be 1.
• Idempotent Falling-1 coupling fault 
between cell i and j : (i) Cell j is to be written with a 1 and read back, (ii) cell i is to be written with 0 and read back, (iii) cell j is to be written with a 0 and read back, and (iv) value at cell i is to be read and checked to be 0.
The same test procedure is to be repeated for all combinations of coupled and coupling cells in the memory.
3.4 Bridging faults
Like coupling faults March tests cannot detect all bridging faults. As discussed in Section 2.4, are the 
four types of AND bridging faults possible. This implies that cells i,j which are involved in bridging faults must have the four combinations of inputs 00,01,10 and 11. From Figure 12 and Figure 13, it may be noted that no cell pairs have all the four combinations 00,01,10 and 11. So to test bridging faults the following test pattern sequences are required.
• AND bridging fault ANDbƒij (involving cells i and ,j): (i) write 0 in cell i and 0 in cell ,j and read back the values (which must remain same), (ii) write 0 in cell i and 1 in cell ,j and read back the values, (iii) write 1 in cell i and 0 in cell ,j and read back the values, and (iv) write 1 in cell i and 1 in cell ,j and read back the values.
It may be noted that the above four test pattern sequence are enough to test OR bridging fault also because we write all possible combinations in the two cells (involved in fault) and read back to check if they retain their values.
3.5 Neighborhood pattern sensitive coupling faults (NPSF)
Similar to the case of bridging and coupling faults, March tests cannot detect NPSFs. For each NPSF we need a particular sequence (according to the one given in the fault) to be given in the neighboring cells of the cell under test. Also the cell under test is to be written in a way such that fault is sensitized. Finally, we need to make the transition(s) in the pattern(s) in the neighboring cells and verify the value in the cell under test. Now we give example of testing one active NPSF and one passive NPSF (using neighborhood type-1).