What it means
Same as P0586 with the control line shorted to ground. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
How it works
On a vacuum-operated cruise system, the vent solenoid releases vacuum from the throttle servo to reduce or cancel cruise throttle. P0587 sets when the vent-control circuit is lower than expected, commonly because the control wire is shorted to ground.
Common causes
Most likely first.
- Control line shorted to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Symptoms
- Cruise control unavailable or disengages
- Cruise-control buttons may not respond
- Check-engine light
How to diagnose it
- Review freeze-frame and related cruise codes, and confirm the vehicle has a vacuum-operated cruise servo.
- Inspect the vent-solenoid connector and harness for chafing, corrosion, loose pins, or a wire contacting ground.
- Compare the vent-solenoid command and circuit state in scan-tool data, if available, while requesting cruise cancel or speed reduction.
- With the circuit isolated as specified, check the vent-control wire for a short to ground.
- Test the vent solenoid and module output using the manufacturer's procedure if no wiring short is found.
Common fixes
- Secure the vent-control harness away from grounded surfaces and sharp edges.
- Repair the vent-control wire shorted to ground.
- Clean or replace corroded or loose vent-solenoid connector terminals.
- Replace the vent solenoid if it fails the manufacturer's test.
- Repair or replace the module only after verifying the wiring and solenoid.
Can I keep driving?
Avoid using cruise control until the vent circuit is repaired because it helps release vacuum from the throttle servo. Normal accelerator driving is usually possible, but if cruise does not cancel normally, use the brake or cancel control and stop safely.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.