What it means
Same as P05E3 with the signal 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
The park-brake switch or position sensor sends its status over a signal circuit monitored by the control module. This low-circuit code sets when the signal voltage is lower than expected, commonly because the signal is shorted to ground or a connection is faulty.
Common causes
Most likely first.
- Signal shorted to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Symptoms
- Park-brake warning light or message may behave incorrectly
- Check-engine or brake warning light may illuminate
How to diagnose it
- Save freeze-frame data and watch live park-brake status while applying and releasing the brake to confirm the low signal is present.
- Inspect the park-brake sensor connector for water, corrosion, bent terminals, or pins pushed back into the housing.
- Trace the signal wire for chafing or crushed insulation that could let it contact ground, especially near brackets and moving parts.
- With the circuit isolated as directed by the wiring diagram, check for an unintended short to ground and compare readings with the manufacturer's specification.
- If no harness short is found, test the switch or sensor and its ground and supply connections against the manufacturer's specification.
Common fixes
- Dry and reconnect a wet or loose sensor connector.
- Clean or repair corroded or pushed-back terminals.
- Repair the signal wire where it is chafed or shorted to ground.
- Replace a park-brake switch or position sensor that fails testing.
Can I keep driving?
A short to ground can make the park-brake indication unreliable, so verify the brake is fully released before driving and avoid relying on hill-hold or stop-start behavior. Stop if the brake warning stays on or the brake does not release cleanly.
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.