P0584
UniversalCruise Control Vacuum Control Circuit High
The engine control system has detected an electrical signal higher than expected in the cruise-control vacuum control circuit. In systems that use vacuum, the control components regulate vacuum to help adjust the throttle and maintain the selected speed. This code does not prove that a particular part has failed; cruise control may stop working or behave inconsistently, though there may be no noticeable symptoms.
⚠️ Before You Begin (Safety First)
Do not rely on cruise control until the issue is diagnosed; control speed manually and be ready to brake. If the vehicle accelerates unexpectedly or cruise control cannot be cancelled normally, brake, move to a safe place, and have the vehicle inspected before continuing.
Common Symptoms
- Cruise control may not set or may be unavailable because the control system has detected an abnormal circuit condition.
- Cruise control may fail to maintain the selected speed if the vacuum control system cannot adjust the throttle as intended.
- Cruise control may operate inconsistently, depending on the circuit fault and system design.
- There may be no noticeable symptoms if the fault does not prevent cruise-control operation.
Common Causes
- Damaged wiring or a short to a higher-voltage source may make the monitored circuit signal higher than expected.
- A loose, damaged, or corroded connector can disturb the circuit signal.
- An open or high-resistance connection may produce an unexpectedly high reading in some circuit designs.
- A fault in the vacuum control solenoid or another cruise-control electrical component may affect the circuit.
- A control-module or circuit issue may be involved; the code does not identify which component is responsible.
Diagnostic Steps
- Check the owner's manual for the vehicle's cruise-control instructions and note whether cruise control is unavailable or behaving differently.
- With the vehicle safely parked and the engine off, visually inspect accessible cruise-control wiring and connectors for looseness, damage, or corrosion; do not disconnect components while the system is operating.
- If the vehicle has accessible vacuum hoses for cruise control, look for obvious disconnection, cracking, or damage without removing hoses or reaching near hot or moving parts.
- Have the code read and recorded before it is cleared. Clearing it without diagnosis may remove useful information without resolving the cause.
- If cruise control behaves unpredictably, stop using it and arrange professional diagnosis.
When to Call a Professional
A technician can confirm the code and check related codes, review available scan data, and test the cruise-control circuit using the vehicle's wiring information. Inspection may include connectors, wiring, the vacuum control solenoid, and relevant vacuum components. The meaning of a high reading depends on the circuit design, so the code alone is not a reason to replace a part.
Compare component listings
Confirm diagnosis and vehicle fitment before buying. A listing does not prove that a part needs replacement. We may earn a commission from qualifying purchases.
Commonly Asked Questions
Does P0584 mean the vacuum solenoid must be replaced?
No. It identifies a high condition in the cruise-control vacuum control circuit, not a confirmed failed part. Wiring, connectors, the solenoid, or another circuit component may need to be checked.
Does “circuit high” mean a vacuum leak?
Not by itself. “Circuit high” describes the electrical condition detected by the control system. A vacuum problem can affect cruise operation, but the code does not establish that a vacuum leak is present.
Can I drive with P0584?
The vehicle may remain drivable, but do not rely on cruise control. If the vehicle accelerates unexpectedly or cruise control cannot be cancelled normally, move to a safe place and seek inspection.
Can this code appear without symptoms?
Yes. A detected circuit condition may not noticeably affect cruise control in every case. The code and the vehicle's actual operation both help guide diagnosis.
What should be checked to diagnose P0584?
A technician can review related codes and scan data, then inspect and test the relevant wiring, connectors, vacuum control components, and circuit using vehicle-specific service information.
Browse Available Code Guides
Previous and next available guides in database record order, across makes. Adjacent entries may share a code number and do not necessarily describe related faults.