P0590Cruise Control Multi-Function Input B Circuit Stuck
- Generic OBD-II code · Powertrain
- How the car detects it
- Cruise control buttons form a resistor ladder on one or two signal lines, each button giving its own voltage window. FCA uses two lines with offset windows – signal 1 is input A, signal 2 input B – and both must report the same button; GM evaluates the ratio to the reference. Any fault locks out cruise control; CARB treats this as emission-neutral, and GM and Ford set these codes without warning lamp. P0590 means input B reports a pressed button permanently – a button stuck or a voltage hanging in one window. No manufacturer document available to us uses P0590; FCA reports a stuck button with its own code P1593 or with P0585, and GM has no stuck code for input B. Counterpart of P0578 for input A.
- What you may notice
- Cruise control cannot be engaged, button noticeably sticking
- Cruise control locked out
- No check engine light
- Likely causes
- LikelyButton stuck mechanically (trim, dirt, spilled drink)
- PossibleShort in the button block's resistor ladder
- PossibleMoisture or corrosion in the switch
- RareModule
- Repair
- Easy · Usually a job for a workshop.Typical cost: €0 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.