P0585
UniversalThe Powertrain Control Module (PCM) detects an implausible correlation or inconsistency between the primary and secondary input signals received from the cruise control multi-function input switch.
Low SeverityThis code indicates that the vehicle's computer has detected an inconsistent signal or a conflict between two different input signals from the cruise control multifunction switch. This electrical discrepancy prevents the cruise control system from operating correctly, making it impossible to set or maintain a desired speed.
⚠️ Before You Begin (Safety First)
Always exercise caution when working on vehicle electrical systems. Before attempting any repairs, ensure the vehicle is turned off, and for most electrical work, it is advisable to disconnect the battery to prevent accidental shorts or injury. Consult your vehicle's service manual for specific safety procedures.
Common Symptoms
- Cruise control not engaging or disengaging
- Check Engine Light (CEL) illuminated
- Intermittent cruise control functionality
- Other dash warning lights related to electrical systems (less common)
Common Causes
- Faulty cruise control multifunction switch
- Wiring harness issues (chafed, broken, corroded wires) to the cruise control components
- Poor electrical connection at the switch or module
- Failed Cruise Control Module (less common)
- Blown fuse affecting the cruise control circuit
Frequently reported on: General/Universal
Diagnostic Steps
- Visually inspect the cruise control multifunction switch and its wiring for any obvious damage or loose connections.
- Check all fuses related to the cruise control system in both the under-dash and under-hood fuse boxes.
- If accessible, test the continuity and resistance of the cruise control switch inputs using a multimeter (refer to service manual for specifications).
- Clean any corroded electrical connectors involved in the cruise control circuit.
- If a replacement switch is available, try replacing the cruise control multifunction switch.
👨🔧 When to Call a Professional
If basic checks like fuses and visible wiring don't resolve the issue, or if you're not comfortable performing electrical diagnostic tests with a multimeter, it's best to consult a professional technician. They have specialized tools and knowledge to accurately diagnose complex electrical correlation issues within the cruise control system.
Commonly Asked Questions
Is it safe to drive with a P0585 code?
Yes, it is generally safe to drive with a P0585 code as it primarily affects the cruise control system and does not impact essential vehicle operations like steering, braking, or engine performance.
What is the most common cause of a P0585 code?
The most common causes are a faulty cruise control multifunction switch or issues with the wiring harness connected to the switch or cruise control module. Less commonly, the cruise control module itself can fail.
Can I fix the P0585 code myself?
Many DIY mechanics can troubleshoot and fix this code. Basic steps include checking fuses, inspecting wiring, and potentially replacing the cruise control switch. Advanced electrical diagnostics might require a multimeter and a service manual.
How much does it cost to fix a P0585 code?
Costs vary, but a replacement cruise control multifunction switch typically ranges from $50 to $200 for the part. If professional diagnosis and repair are needed, labor costs can add another $100-$300 or more, depending on the shop and complexity.
Will fixing the cruise control switch clear the P0585 code?
In most cases, if a faulty cruise control switch is the root cause, replacing it will resolve the issue and allow the code to be cleared by the vehicle's computer, or you may need to clear it with an OBD-II scanner.