The P0577 code on your 2020 Ford Escape indicates a high voltage condition in the cruise control input circuit. High voltage typically suggests an open circuit preventing proper signal transmission.
High Input Analysis
When the cruise control input reads high voltage, it indicates the circuit isn't completing to ground through the switches. The PCM sees reference voltage because no switch is loading the circuit—either all switches are open, or the circuit itself is broken.
Escape Cruise Control
The 2020 Ford Escape features standard cruise and available adaptive cruise control. Both systems use the same switch inputs. An open circuit affects all cruise control functions since no switch signals can reach the PCM.
Open Circuit Causes
A disconnected connector creates an open. Broken wiring prevents signal path completion. The clock spring may have an open circuit in the cruise lines. All switches could theoretically be stuck open, though this is rare. Corroded terminals may have enough resistance to read as open.
Diagnostic Process
Use Ford IDS to verify high voltage on cruise input. Press cruise buttons—voltage should drop when any switch closes. If it stays high regardless of button press, the circuit is open before the switches. Check connector continuity. Test clock spring for opens. Verify switch assembly connections.