Electric E-brake Key Switch Circuit Failure
There's a failure in the electric emergency brake switch circuit.
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 computer is not getting the right signal from the emergency brake switch, which might be stuck or broken. It should see a closed circuit when the brake is applied, typically around 0 volts for 'on' and about 12 volts for 'off'.
What the computer is actually seeing
The vehicle's computer expects a signal of near 0 volts when the brake is engaged and around 12 volts when disengaged. A voltage outside this range indicates a problem with the switch or wiring.
What a healthy reading looks like
0 volts (brake applied) / 12 volts (brake released)
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.
- 11. Check the wiring and connectors at the emergency brake switch for any visible damage or corrosion.
- 22. Use a multimeter to measure voltage at the switch connector. With the brake applied, you should see near 0 volts. If not, inspect the wiring from the switch to the ECM for shorts or breaks.
- 33. If the wiring is okay, test the electric emergency brake switch directly. You should see continuity (close to 0 ohms) when the switch is activated and infinite resistance when it's not active. If it's faulty, replace it.
- 44. Clear the code and test drive the vehicle. If the code returns, recheck the connections and the switch itself.
Common causes
- Faulty electric emergency brake switch
- Wiring issue or short circuit in the switch harness
- Corroded connectors at the switch or in the circuit
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
You can drive the vehicle, but be cautious as you won't have a functioning electric emergency brake.
Will the code come back after repairs?
If the underlying issue is properly fixed, the code should not return.
Why does this code pair with others like C0279?
Codes can indicate various issues in the same system, often pointing to interconnected components like the switch or circuit.
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