What Does C1157 Mean?
This code indicates the control module has detected a circuit failure in the park brake actuator assembly switch applied position circuit. The park brake actuator switch monitors whether the electronic or mechanical parking brake is in the applied (engaged) position. When this circuit fails, the module cannot confirm parking brake status, which affects ABS operation and dashboard indicator lamp logic.
Common Causes
35%
Failed park brake actuator position switch due to mechanical wear or internal contact degradation
25%
Corroded or damaged wiring at the park brake mechanism exposed to road spray and moisture
20%
Loose or corroded connector at the actuator switch preventing reliable signal
15%
Misadjusted or worn park brake mechanism causing the switch to be out of its detection range
5%
Control module internal failure on the park brake switch input
Diagnostic Steps
1
Step 1: Apply and release the parking brake while monitoring the park brake indicator on the dashboard. If the indicator does not change state, the switch circuit is confirmed faulty.
2
Step 2: Locate the park brake actuator switch and disconnect its connector. Measure continuity across the applied position terminals while manually engaging the parking brake. The switch should toggle cleanly.
3
Step 3: With the switch connected, backprobe the signal wire and verify proper voltage change at the control module when the parking brake is applied and released.
4
Step 4: Check wiring continuity from the switch connector to the control module. Test for opens, shorts to ground, and shorts to battery.
5
Step 5: Repair or replace the faulty switch, clear codes, and cycle the parking brake several times to verify proper operation.
Estimated Repair Cost
$80 - $350
Parts + labor, varies by vehicle and location
This code indicates the control module has detected a circuit failure in the park brake actuator assembly switch applied position circuit. The park brake actuator switch monitors whether the electronic or mechanical parking brake is in the applied (engaged) position. When this circuit fails, the mod...
The most common cause of C1157 (Park Brake Actuator Assembly Switch Applied Circuit Failure) is: Failed park brake actuator position switch due to mechanical wear or internal contact degradation
Typical repair costs for C1157 range from $80 to $350, depending on the vehicle, location, and whether you do it yourself or go to a shop.
The module cannot confirm parking brake status, which may affect ABS calibration and warning lamp operation. Vehicle is safe to drive but parking brake indicator may be unreliable. Repair within one week.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to C1157 to identify the root cause.
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Quick Info
Category
Chassis
System
Parking Brake System / ABS
Difficulty
Type
Manufacturer
Recommended Tools
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