A novel and pragmatic Built-in Self Test technique provides cost-effective and thorough testing and diagnosis of content addressable memories (CAMs). The method is particularly attractive for write-only CAMs, as neither the presence of a read port nor direct observability of CAM match -lines are required or testing. The underlying test algorithm uniquely exploits little known inherent properties of pseudorandom patterns generated by linear feedback shift registers in a test-time and hardware-efficient BIST implementation.