Park Brake Switch A Circuit
Fault in the park brake switch circuit detected.
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 park brake switch sends a signal when the brake is applied. If this signal is incorrect, the system thinks the brake isn't on, which could interfere with safety features.
What the computer is actually seeing
The ECM looks for a voltage signal between 0.5V to 2.5V when the park brake is engaged; it should be near 0V when disengaged. If the signal stays high or shows an intermittent fault, it triggers this code.
What a healthy reading looks like
0.5V - 2.5V when engaged; close to 0V when disengaged.
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. Inspect the wiring and connectors to the park brake switch for damage or corrosion. Decision: Are they in good condition? Yes: Go to step 2. No: Repair wiring/connectors and retest.
- 22. Using a multimeter, check the voltage at the park brake switch while engaging the brake. Decision: Is the voltage within 0.5V to 2.5V when engaged? Yes: Go to step 3. No: Replace the park brake switch.
- 33. Check for any fault codes related to the brake system, especially if any wiring repairs were made. Decision: Are there other codes present? Yes: Diagnose and repair those codes. No: Clear the codes and retest the system.
Common causes
- Faulty park brake switch
- Wiring issues in the park brake circuit
- Corroded or damaged connectors
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderate severity. You may experience brake system issues, so fix it soon.
Will this code come back after clearing it?
If the problem isn't fixed—like a bad switch or wiring—it will likely come back.
Why does this code pair with other codes?
Related codes can indicate issues in similar systems, often the same circuit or switch failures.
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