This message tells you that a TSTQ block function code 31 is being used to test a signal that does not have the Quality attribute, or the signal being tested has no quality to propagate. The input will never be found to have bad quality and no action will happen that might be intended.
As of DBDOC 10.4, signals that have quality are represented in DBDOC as blue or purple lines on CAD and CLD diagrams. Function codes that have quality or propagate the quality of their input are listed at Function codes with quality.
This message sometimes appears where macros have been taken to implement logic, so it might not be an error. However, we often find such oversights as testing the quality of an Analog Tranfer function block instead of its intput, or the quality of a digital logic block rather than the inputs or outputs to the block.
Regarding function code 68, this is documented as an error because we have found that people appear to think there is quality attached to function code 68, the REMSET block, when there is not. Since the REMSET block should be set by hand, some people thought it was bad quality until that happened, which is not documented. Also, we found many places where the FC 68 block was on a different page from where it was being tested, so it was not visible by inspection that the block did not have quality.
--Post Processing drawing T CCW Pumps Auto Trip TSTQ Module 1,02,10 Block 6031 tests Module 1,02,10 Block 5663 (FC 38), which does not have quality --Generating Effective Quality report... TSTQ Module 1,02,10 Block 6030 tests Module 1,02,10 Block 5615 (FC 67), which is not propagating quality
Related DBDOC messages are DBDOC-CHECK_TSTQ.ERR, where the signal comes from a constant, and DBDOC-CHECK_TSTQ_COMMUNICATION_ONLY.ERR, where the signal being tested doesn't have quality but has quality from communication.
It is very important to note that this error will only cause a problem when a signal that is counted upon goes bad quality and the logic fails to detect that problem. It was missed in checkout and commissioning, or in subsequent work because it cannot be tested validly.
This error can be built directly into Hyperview. For more information, see the article Building error reports into the M14.