P07B5: Park switch A sits between valid button states

P07B5 is a Park-button switch A performance code in the GM table reviewed here. Its distinctive feature is an intermediate signal range: the controller sees a reading that belongs to neither the valid pressed zone nor the valid released zone.

Why this differs from high or low

The malfunction interval is above 184.00 and below 188.00 in the source's signal scale. The table does not identify those numbers as volts. The monitor is therefore concerned with an unrecognized state within that narrow interval, rather than simply using the lowest or highest possible reading.

Qualification is also relatively persistent: 400 failing samples within 480 samples. No loop interval is printed on this row, so the count cannot responsibly be turned into a fixed number of seconds by borrowing timing from another code. The reporting class is Type B over two trips.

Interpreting the prerequisite faults

The enable column references the switch A low and high codes, P07B3 and P07B4, as faults not set, and requires calibration enablement. This makes their status relevant when deciding whether the performance monitor had a valid opportunity to run; they are not additional definitions of P07B5.

Review the button-state transitions and measured switch A value together. A signal that repeatedly occupies the undecided zone can explain this monitor even when the input never reaches an extreme. Verification must show recognized pressed and released states under the applicable test. The source does not establish mechanical Park engagement, a failed part, or universal vehicle applicability.

Source: GM monitor, PDF page 648.