Cruise Control Multi-Function Input Circuit Malfunction
The P0589 code indicates a problem in the cruise control multi-function input circuit. This circuit carries signals from the steering wheel controls (set, resume, cancel) to the powertrain control module (PCM). A fault can be caused by a short, open, or high resistance in the wiring, a faulty switch, or a PCM issue. The system may not respond to inputs or may engage/disengage unexpectedly.
01. Most Common Causes
- Faulty cruise control switch
- Damaged wiring or connector in the multi-function input circuit
- Corrosion or poor ground connection
- Failed PCM (rare)
02. Symptoms You Will Notice
- Cruise control inoperative
- Cruise control does not set, resume, or cancel
- Cruise control engages or disengages randomly
- Check engine light illuminated
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to verify the code and check for additional codes.
Step 2: Visually inspect the cruise control switch and wiring for damage or corrosion.
Step 3: Test the switch continuity with a multimeter according to manufacturer specs.
Step 4: Check the circuit for shorts, opens, or high resistance between the switch and PCM.
Step 5: If all else is fine, test the PCM for proper operation (rare).
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, but cruise control will be disabled or erratic. The vehicle remains drivable.
How much does it cost to fix?▼
Typically $50-$150 for diagnosis and switch replacement. PCM replacement is more expensive.