What it means
Cruise Control Multi-Function Input A Circuit: an electrical fault is present in the circuit. This affects cruise-control operation.
At a glance
- Usually lights the check-engine light
How it works
The cruise-control multi-function switch sends an Input A command through a circuit to the control module. P0564 sets when the module detects an electrical fault in that Input A circuit, which can prevent it from recognizing the switch command.
Common causes
Most likely first.
- Cruise control multi-function switch or stalk failed
- Open, short, or damaged wiring
- Loose or corroded connector
- Fault in the related control module
Symptoms
- Cruise control may not engage or may stop working
- Cruise control buttons may respond inconsistently
- Check-engine light may come on
How to diagnose it
- Check freeze-frame data and scan for other cruise-control or switch-input codes to learn when Input A failed and whether related inputs are also affected.
- Use live data, if available, to see whether the cruise-control Input A status changes when its switch or stalk is operated.
- Inspect the cruise-control switch or stalk connector and the wiring along the steering column for loose pins, corrosion, chafing, or damage.
- With the wiring diagram, test the Input A circuit for an open, short, or poor connection while operating the switch.
- If the switch circuit tests correctly, follow the manufacturer's procedure to check the receiving control module and its power and grounds.
Common fixes
- Reconnect, clean, or repair a loose or corroded Input A connector.
- Repair an open, shorted, or chafed wire in the cruise-control switch circuit.
- Replace a failed cruise-control multi-function switch or stalk.
- Repair the related control module or its connections if circuit tests isolate the fault there.
Can I keep driving?
You can usually drive without cruise control, but do not rely on it until the fault is repaired. If cruise control engages or behaves unpredictably, switch it off and avoid using it.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.