P0564 Cruise Control Multi-Function Input A Circuit

P0564 indicates a cruise control multi-function input A circuit issue. The controller is receiving an invalid or missing signal from the cruise switch input group.

Code details

Generic OBD-II · P0

System: Speed / Idle
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not replace the cruise module before checking switch input data, brake switch status, and steering column wiring.

Symptoms of P0564

Unstable, high, or low idle, or stalling.
Erratic speedometer, cruise-control, or shift behaviour.
Check-engine light with a hesitation or surge.

Common causes of P0564

A dirty throttle body, idle-control valve, or throttle-position sensor.
A failing vehicle-speed or wheel-speed sensor, or its wiring.
Vacuum leaks or a related sensor forcing the idle/speed strategy.

Useful checks before replacing parts

Compare cruise switch input states, brake switch data, clutch or neutral inputs, vehicle speed, steering wheel controls, and freeze-frame conditions.
Inspect switch contacts, clockspring wiring, steering column connectors, shared reference or resistor ladder circuits, moisture intrusion, and module communication.
Operate each cruise switch while watching live data to confirm input A changes only when commanded.

Related OBD-II codes

These nearby speed / idle entries can help compare wording and pin down the fault area.