Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble communicating with a sensor that listens for unusual engine noises on one side of the engine.
The P135C code is triggered when the Engine Control Module (ECM) detects a problem with the signal from the second knock sensor on bank 1 of the engine.
The knock sensor is responsible for detecting engine knocking or pinging, which can cause damage. This sensor sends signals to the ECM to adjust engine timing and prevent knocking. A circuit issue means the ECM is not receiving the expected signal from the sensor.
• Check Engine Light illuminated
• Poor engine performance
• Increased fuel consumption
• Faulty knock sensor
• Wiring issues or poor connections in the knock sensor circuit
• Faulty Engine Control Module (ECM)
ECM: Engine Control Module
Knock Sensor: A sensor that detects engine knocking
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the knock sensor.
• Test the knock sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty knock sensor.
• Update or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regular engine maintenance
• Ensure proper fuel quality
• Routine inspection of engine sensors
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
Check with your vehicle manufacturer for specific warranty coverage on sensors.
This code has been associated with faulty sensor issues due to wear and tear over time.
Moderate – Addressing this issue promptly can prevent further engine damage.
Driving with a faulty knock sensor can lead to engine damage and is not recommended.
• Engine at operating temperature
• Vehicle stationary
The knock sensor is typically located on the engine block, cylinder head, or intake manifold.
Q: Can I drive with a P135C code?
A: It's not recommended as it can lead to engine damage.
Q: How do I reset the Check Engine Light after repair?
A: Use an OBD-II scanner to clear the code after repairs are complete.
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