What it means
Same as P05E3 with intermittent or erratic signal. 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
The park-brake switch or position sensor sends brake status to the control module, which monitors the signal for stable changes as the brake is used. This intermittent or erratic code sets when that signal drops out or fluctuates unpredictably rather than changing consistently with brake movement.
Common causes
Most likely first.
- Intermittent contact at connector
- Connector with intermittent contact under vibration
- Harness routed against vibrating component
Symptoms
- Park-brake warning light or message may flicker or behave inconsistently
- Check-engine or brake warning light may illuminate
How to diagnose it
- Review freeze-frame data and watch live park-brake status while applying and releasing the brake to see whether the signal flickers.
- With the status data visible, gently move the sensor connector and nearby harness to check for a repeatable dropout.
- Inspect connector terminals and seals for looseness, corrosion, moisture, or signs of vibration-related movement.
- Trace the harness where it touches brackets or vibrating components and check for chafing, strain, or a loose clip.
- If the harness stays stable, test the switch or sensor output during repeated brake movement against the manufacturer's specification.
Common fixes
- Reseat and secure a loose sensor connector.
- Clean or repair terminals with corrosion or poor contact.
- Secure or reroute a harness that rubs or vibrates against another component.
- Repair intermittent wiring damage or replace a switch or sensor that drops out during testing.
Can I keep driving?
The warning may come and go while the park-brake status is unreliable, so confirm the brake is fully released before moving and do not depend on hill-hold or stop-start behavior. Stop if the brake warning stays on or the brake begins to drag.
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.