Parking Brake Release Switch Circuit Failure
The C1177 code indicates a fault in the parking brake actuator release switch circuit. According to SAE J2012 and manufacturer service manuals, the control module (such as the parking brake module or PCM) has detected an electrical anomaly in the switch signal when the actuator is in the released position. This typically occurs when the circuit voltage or resistance deviates from expected parameters, preventing the module from confirming that the parking brake is fully disengaged.
1. Commonly Affected Makes
2. Most Common Causes
- Faulty or stuck parking brake release switch
- Open or short-to-ground wiring in the circuit
- Corroded or loose electrical connections at the switch or module
- Internal failure of the parking brake control module (PAM)
- Blown fuse in the switch power supply circuit
3. Symptoms You Will Notice
- Parking brake warning light illuminated on the dashboard
- Parking brake may not release or engage properly
- Reduced functionality of electronic parking brake system
4. Step-by-Step Diagnosis
Scan for additional codes and check freeze frame data
Inspect the parking brake release switch and its wiring for damage or corrosion
Test switch continuity and resistance with a multimeter
Check for proper voltage and ground at the switch connector
Inspect the parking brake control module for signs of failure
5. Frequently Asked Questions
Is it safe to drive?▼
It is generally safe to drive short distances, but the parking brake may not function correctly. Have the system inspected as soon as possible to avoid potential safety issues.
How much does it cost to fix?▼
Repair costs typically range from $100 to $400, depending on whether the switch, wiring, or control module needs replacement.