C1954 – OBD-II DTC

OBD-II DTC C1954 – Master Cylinder Pressure Sensor Circuit Failure

DTC C1954 meaning

DTC C1954 refers to a fault in the Master Cylinder Pressure Sensor Circuit. This diagnostic trouble code indicates that the vehicle’s onboard diagnostic system has detected an issue with the pressure sensor that monitors the hydraulic pressure in the master cylinder. The master cylinder is a crucial component of the braking system, and its pressure sensor provides vital information to the vehicle’s electronic control unit (ECU) for proper brake function.

DTC C1954 symptoms

Common symptoms associated with DTC C1954 may include:

• Illuminated warning lights on the dashboard, such as the brake warning light.
• Inconsistent or erratic brake performance.
• Increased stopping distances.
• Unusual noises when applying brakes.
• Potential activation of the anti-lock braking system (ABS) warning light.

DTC C1954 causes

Several factors can lead to the occurrence of DTC C1954, including:

• Faulty master cylinder pressure sensor.
• Wiring issues, such as damaged or corroded connectors.
• Short circuits or open circuits in the sensor circuit.
• Faulty electronic control unit (ECU).
• Fluid leaks in the braking system affecting pressure readings.

DTC C1954 seriousness

DTC C1954 is considered a serious issue as it directly impacts the vehicle’s braking system. If left unaddressed, it can lead to:

• Reduced braking efficiency.
• Increased risk of accidents due to brake failure.
• Potential damage to other braking system components.

It is crucial to diagnose and repair this issue promptly to ensure safe vehicle operation.

How to diagnose DTC C1954

To diagnose DTC C1954, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1954 code.
2. Inspect the master cylinder pressure sensor and its wiring for visible damage or corrosion.
3. Check for any additional trouble codes that may provide more context.
4. Test the voltage and ground at the sensor connector using a multimeter.
5. Perform a functional test of the master cylinder pressure sensor to ensure it operates within specifications.

How to fix DTC C1954 step-by-step instructions

To fix DTC C1954, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on the electrical system.
2. Inspect and repair any damaged wiring or connectors related to the master cylinder pressure sensor.
3. If the sensor is faulty, replace it with a new one, ensuring it is compatible with the vehicle.
4. Reconnect the battery and clear the DTC using an OBD-II scanner.
5. Test drive the vehicle to ensure the issue is resolved and monitor for any reoccurrence of the code.

How to erase DTC C1954

To erase DTC C1954, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the vehicle to ensure the code does not return.

Recommended tools for OBD-II diagnostics

Explore our expert picks: The Best OBD2 Scanners for 2025

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.