P0590 Code: Cruise Control Multi-Function Input B Circuit Stuck
The P0590 code means the computer sees a fault in the signal from the cruise control switches, with multi-function input B stuck. Cruise control is disabled, and the rest of the vehicle works normally. A worn clockspring or a sticking button is the usual cause.
- Severity
- Low
- Can I keep driving?
- Yes, no immediate risk
- Estimated cost
- $20 to $400
- Difficulty
- Medium
- System
- Idle and Speed Control
- Applies to
- All OBD2 vehicles
On this page
What the P0590 code means
The cruise control switches, on the steering wheel or on a stalk, send their orders to the computer over one or more wires. Many manufacturers use one line with a different resistance for each button, and the computer recognizes the pressed button by the voltage it measures.
The P0590 code means the computer sees a signal that matches no button, a signal that stays fixed as if a button were held down all the time (the stuck condition), or a signal that does not agree with the second control line. For safety, it disables cruise control.
The most common cause is the steering wheel clockspring, which connects the buttons to the vehicle through a ribbon that wears as the wheel turns. Buttons that are dirty or soaked with spilled liquid are another usual cause.
Always start with the simple checks: fuse, relay and connector. Then check power, ground and signal with the component connected (using back-probe pins), and finally the continuity of each wire to the computer. Replace the component only if all of that is good.
P0590 code symptoms
- Cruise control that does not work.
- Check engine light or cruise control light on.
- Sometimes the horn or the steering wheel buttons also fail (clockspring).
Likely causes of the P0590 code
- Damaged steering wheel clockspring. The internal ribbon breaks with use.
- Steering wheel buttons that are dirty or damaged by spilled liquids.
- Control module connector with a loose, intermittent contact.
- Brake switch, if it affects the cancel signal.
How to diagnose the P0590 code step by step
- Read the status of each button on the scan tool while you press it. Only the pressed button should change.
- Measure the resistance of the controls in each position and compare it with the manufacturer table.
- Inspect the clockspring if the horn, the airbag light or the steering wheel buttons also fail.
- Check the brake switch.
How to fix the P0590 code
- Replace the clockspring or the steering wheel controls.
- Clean the button contacts.
- Repair the wiring.
- Clear the code and test cruise control.
Technical reference data
- Resistor ladder controls: each button gives a different voltage on the same line.
- Reference values only: check the manufacturer data for your vehicle.
Brand-specific notes
Before you work on the steering wheel, disconnect the battery and wait a few minutes. The driver airbag can deploy.
P0590 on Ford
The clockspring is a frequent fault on many Ford vehicles.
P0590 on GM
The clockspring is a frequent fault on many GM vehicles.
P0590 on Chrysler
The clockspring is a frequent fault on many Chrysler vehicles.
Questions about the P0590 code
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