Electric Parking Brake (EPB) Switch Fault
The vehicle's electronic parking brake system has detected a fault with the switch.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The electronic parking brake can't tell if the switch is working right, which means the brake may not release or engage properly.
What the computer is actually seeing
The electronic control module (ECM) is monitoring the parking brake switch input voltage. If the voltage is out of expected range (0V or 5V) when the switch is activated, it sets the C1031 code.
What a healthy reading looks like
When the parking brake switch is pressed, the signal should show around 5V; when released, it should drop to around 0V without any delay.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the parking brake switch for physical damage or sticking.
- 2Inspect the wiring and connectors for any signs of corrosion or damage.
- 3Use a multimeter to measure the voltage at the parking brake switch: should see 0V when released and close to 5V when pressed. If not, replace the switch.
- 4If the switch is fine, check for continuity and proper ground in the wiring leading to the ECU.
Common causes
- Faulty parking brake switch
- Wiring issues (short or open circuits)
- Corrosion in connectors
- Faulty electronic control unit (ECU)
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code present?
Yes, but be aware that your parking brake may not work properly, so it's best to fix it soon.
Will this code come back after clearing it?
It might, especially if there's an underlying issue with the switch or wiring.
Why does this code pair with C1030?
C1030 indicates a different fault in the electronic parking brake system, often related to the same components.
Working a real vehicle right now?
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