P0564Cruise Control Multi-Function Input A Circuit
- Generic OBD-II code · Powertrain
- How the car detects it
- Cruise control buttons are almost always a resistor ladder on one or two signal lines, each button giving its own voltage; the module reading it (GM and Saab from about 2010: the body module; FCA: steering column module or PCM) sends the button state to the engine module over CAN. CARB names cruise control as the example of an emission-neutral diagnosis – it is simply switched off – so GM lists all these codes as type C and Ford as non-MIL: no warning lamp, the engine runs normally. P0564 watches signal line A of the ladder: only voltage windows matching a button or no button are valid. GM sets it when the ratio sits in a gap between windows for over 0.5 s (2014: 2.5 s), the body module in the Saab 9-4X and 9-5 after an invalid voltage for 2 s. Cruise control is locked out for the ignition cycle.
- What you may notice
- Cruise control cannot be switched on or switches off
- Cruise control locked out
- No check engine light, engine runs normally
- Likely causes
- LikelyCruise or steering wheel switch faulty or dirty (moisture, worn contacts)
- PossibleClockspring or steering wheel connector with contact resistance
- PossibleSupply or signal line to the body module open or shorted
- RareBody module
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.