P0590 – Cruise Control Multi-Function Input “B” Circuit Stuck

P0590 is a diagnostic trouble code that points to a problem with your vehicle’s cruise control switch circuit, usually on the steering wheel or column. When this circuit doesn’t behave the way the ECU expects, it disables cruise control and may turn on the check engine light. While this code won’t usually leave you stranded, it can be annoying on long trips and may indicate an underlying electrical issue. Understanding what P0590 means, how it behaves, and how to fix it will help you decide whether it’s a DIY job or one for a shop.

What Does P0590 Mean?

P0590 is defined as “Cruise Control Multi-Function Input ‘B’ Circuit Stuck.” In simple terms, your engine control unit (ECU) sees one part of the cruise control switch circuit stuck in an ON, OFF, or invalid position when it should be changing.

This usually involves the buttons on your steering wheel or the cruise control stalk. The ECU monitors several different switch inputs (Set, Resume, Cancel, On/Off). When one of those inputs in the “B” circuit doesn’t change voltage or resistance as expected, it logs P0590 and often disables cruise control for safety.

Quick Reference

• Code: P0590 – Cruise Control Multi-Function Input “B” Circuit Stuck
• Severity: Low to moderate (comfort/feature issue, not engine damage)
• Primary system: Cruise control / steering wheel switch circuit
• Typical causes: Faulty cruise switch, broken clockspring, wiring fault, connector corrosion
• Typical symptoms: Inoperative cruise control, warning lights, sometimes other steering wheel buttons failing

Real-World Example / Field Notes

In the shop, I see P0590 most often on vehicles with steering wheel-mounted cruise buttons that have seen years of use, spilled drinks, or heavy cleaning chemicals. A common pattern: the driver complains that cruise works only sometimes, or certain buttons don’t respond. The check engine light may or may not be on. Testing usually shows one button signal stuck at a fixed voltage. Many times, replacing the switch assembly or the clockspring restores all functions. Less often, I find a rubbed-through wire in the steering column or a corroded connector under the dash.

Symptoms of P0590

• Cruise control inoperative – Cruise won’t turn on, set, or hold speed.
• Intermittent cruise operation – Works sometimes, then drops out or refuses to set.
• Non-responsive buttons – Specific buttons like “Set,” “Resume,” or “Cancel” do nothing.
• Check engine light – MIL or a separate cruise control warning light may illuminate.
• Other steering wheel buttons failing – Radio or phone controls may also act up if the clockspring is involved.
• Unexpected cruise cancel – Cruise disengages randomly even though you didn’t touch the brakes.
• Stored cruise-related codes – Additional DTCs for the cruise or steering angle system may appear.

Common Causes of P0590

Most Common Causes

• Faulty cruise control switch assembly: Worn or contaminated contacts inside the steering wheel or stalk switch can cause a stuck or incorrect signal. This is the number one cause.
• Damaged clockspring (spiral cable): The clockspring carries electrical signals through the steering wheel as it turns. Broken internal traces can cause one or more switch circuits to read open or stuck.
• Connector corrosion or loose plug: Moisture, spills, or prior repairs can leave green corrosion or loose pins at the steering wheel, column, or under-dash connectors.
• Wiring damage in steering column: Chafed, pinched, or broken wires where the harness bends with steering movement can interrupt the cruise switch signal.
• Previous accessory installation: Aftermarket radio, remote start, or steering wheel control interfaces sometimes tap into the wrong wires or damage the circuit.

Less Common Causes

• Faulty brake pedal or clutch switch: If these switches send incorrect “brake applied” signals, the ECU may interpret the cruise input as stuck or invalid.
• Internal ECU fault: Rare, but a failing engine or body control module can misread a good switch signal and set P0590.
• Water intrusion in steering column: Leaks from the windshield or cowl can drip onto column wiring and cause intermittent shorts.
• Incorrect parts or programming: Swapped steering wheel, wrong clockspring, or used ECU that wasn’t properly configured can cause mismatched signals.
• Ground or power supply issues: Poor ground or low voltage to the switch reference circuit can make the ECU think the input is stuck.

Diagnosis: Step-by-Step Guide

You’ll want a basic scan tool that can read live data, a digital multimeter, and ideally wiring diagrams for your specific vehicle. A service manual or reliable online repair information will save time. If you’re comfortable removing steering wheel trim and working around airbag components, you can do a lot of this yourself, but always follow safety procedures.

1. Verify the complaint: Try every cruise control button (On/Off, Set, Resume, Cancel) while driving at a safe speed. Note which functions work or fail. See if any other steering wheel buttons act up.
2. Scan for codes: Use a scan tool to check for P0590 and any related DTCs (cruise, brake switch, steering angle, or clockspring codes). Record freeze frame data to see when the fault occurred.
3. Check live data for switch inputs: Many scan tools show cruise switch status in real time. Press each button and watch for changes. A line that never changes (always ON or always OFF) is your suspect circuit.
4. Inspect steering wheel controls: With the key off and battery disconnected (airbag safety), remove the steering wheel trim as needed. Look for signs of liquid spills, cracked buttons, or physical damage.
5. Inspect clockspring and connectors: Check the clockspring connectors for bent pins, corrosion, or broken locking tabs. Gently wiggle the harness while watching live data to see if the signal cuts in and out.
6. Test switch resistance/voltage: Using the wiring diagram, back-probe the cruise switch wires. Most systems use different resistances for each button. Press each button and compare readings to spec. A stuck or out-of-range value indicates a bad switch or clockspring.
7. Check wiring continuity: If the switch and clockspring test good, perform continuity and wiggle tests from the steering column connector to the ECU or body control module. Repair any open or shorted wires.
8. Confirm brake/clutch switch operation: Verify that brake and clutch switches change state correctly in live data. A stuck “brake applied” signal can cause the ECU to disable cruise and set related codes.
9. Clear codes and road test: After repairs, clear P0590 and drive while using cruise control. Confirm that all buttons work and the code does not return.

Pro tip: If multiple steering wheel functions (airbag light, horn, audio controls) are acting up along with P0590, suspect the clockspring first. It’s a common failure point and often easier to replace than chasing intermittent wiring faults.

Possible Fixes & Repair Costs

The exact repair depends on what you or your technician find during diagnosis, but most P0590 fixes are in the electrical and control side, not the engine itself.

• Replace cruise control switch assembly: On many vehicles this is part of the steering wheel button cluster or stalk. Parts typically run $50–$200, with labor $80–$200 depending on access.
• Replace clockspring (spiral cable): Common fix when multiple steering wheel functions fail. Parts usually $80–$250, labor $150–$350 because the airbag and wheel must be removed.
• Repair wiring/connectors: Fixing a broken wire, cleaning corroded terminals, or reseating loose connectors may cost $100–$250 in labor at a shop, depending on how long it takes to access and test.
• Replace brake or clutch switch: If related, these are often $20–$80 for parts, plus $50–$150 labor.
• ECU or body control module replacement: Very rare for P0590 alone. If needed, you’re looking at $400–$1,000+ including programming.

In most cases, you’re looking at a total repair cost in the $150–$500 range at a typical independent shop. Costs vary with vehicle make, parts availability, and how much diagnostic time is required to pinpoint the exact fault.

Can I Still Drive With P0590?

Yes, you can usually keep driving with a P0590 code without risking immediate engine damage. The main downside is that your cruise control may not work, or it may be unreliable. On long highway trips, that can be inconvenient and tiring. You should still get it checked, because in some cases the same clockspring or wiring issue can affect other safety-related systems like the airbag, horn, or steering wheel controls. If you notice any airbag warning lights or other odd behavior, treat it as higher priority.

What Happens If You Ignore P0590?

If you ignore P0590, you’ll likely just live without cruise control, but a small electrical fault can grow into a bigger one. Damaged wiring or a failing clockspring may eventually affect the airbag, horn, or other steering wheel controls. Also, a constantly illuminated check engine light can hide new problems, since you might ignore it when a more serious code appears later.

Last updated: February 13, 2026

Vehicles Commonly Affected by P0590

P0590 shows up across many brands, but it’s especially common on vehicles with heavily used steering wheel controls and complex clockspring assemblies. You’ll often see this code on:

• GM vehicles: Chevrolet, GMC, Buick, and Cadillac trucks and SUVs with steering wheel cruise buttons.
• Ford and Lincoln models: Especially F-150, Escape, Explorer, and similar platforms.
• Hyundai and Kia: Sedans and crossovers with multi-function steering wheels.
• Chrysler, Dodge, Jeep, Ram: Many models that use integrated steering wheel switch packs.
• Japanese brands: Some Toyota, Honda, Nissan, and Subaru models, particularly when the clockspring or steering wheel switches age or see liquid spills.

Any modern vehicle with cruise control and steering wheel buttons can set P0590 if the switch circuit, clockspring, or related wiring develops a fault.