Cruise Control Vent Control Circuit Low
The P0587 code indicates that the powertrain control module (PCM) has detected a low voltage condition in the cruise control vent control circuit. This circuit controls the vacuum release valve that vents vacuum from the cruise control servo, allowing the throttle to close. A low voltage reading suggests a short to ground, open circuit, or faulty component in the vent solenoid circuit, preventing proper cruise control operation.
01. Most Common Causes
- Faulty cruise control vent solenoid
- Short to ground in vent control circuit wiring
- Open circuit in vent control circuit
- Corroded or damaged connector at vent solenoid
- Failed PCM (rare)
02. Symptoms You Will Notice
- Cruise control inoperative
- Cruise control light on dash illuminated
- Engine Check Light (MIL) on
- Cruise control disengages unexpectedly
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to retrieve all codes and freeze frame data.
Step 2: Visually inspect the cruise control vent solenoid and its wiring for damage, corrosion, or loose connections.
Step 3: Test the vent solenoid resistance with a multimeter (typically 20-40 ohms). Replace if out of spec.
Step 4: Check for voltage at the solenoid connector with key on (should be battery voltage). If low, trace circuit for shorts or opens.
Step 5: If wiring and solenoid are good, suspect a PCM fault and perform further diagnostics.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, but cruise control will not work. The vehicle remains drivable, but the Check Engine light may be on.
How much does it cost to fix?▼
Typically $50-$150 for parts and labor, depending on the cause. A vent solenoid replacement is usually under $100.