Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the sensor that checks the vacuum in the brake system. It's like a sensor that tells if there's enough air being sucked out to help the brakes work properly.
The C1031 code indicates an issue with the electrical circuit of the brake system vacuum sensor, specifically Circuit B.
The brake system vacuum sensor monitors the vacuum level in the brake booster. Circuit B refers to a specific part of the sensor's circuitry. An electrical fault in this circuit can lead to improper brake booster operation, affecting braking performance.
• Illuminated brake warning light
• Increased brake pedal effort
• Reduced braking performance
• Unusual noises from the brake booster
• Erratic braking behavior
• Faulty brake system vacuum sensor
• Damaged or corroded wiring or connectors
• Faulty vacuum pump
• Blown fuse related to the sensor circuit
• Malfunctioning electronic control module (ECM)
Vacuum Sensor: A device that measures the vacuum level in a system.
Brake Booster: A component that uses vacuum to help reduce the effort needed to apply the brakes.
• Inspect the brake system vacuum sensor and its wiring for damage.
• Check the electrical connectors for corrosion or looseness.
• Test the vacuum sensor using a multimeter.
• Inspect the vacuum pump for proper operation.
• Check related fuses and relays.
• Replace the faulty brake system vacuum sensor.
• Repair or replace damaged wiring or connectors.
• Replace the vacuum pump if it is malfunctioning.
• Replace any blown fuses.
• Reprogram or replace the ECM if necessary.
• Multimeter
• Vacuum pump tester
• OBD-II scanner
• Wiring repair kit
• Basic hand tools
$150 - $500
Moderate
• Dodge Ram
• Jeep Grand Cherokee
• Chrysler 300
• Regularly inspect brake system components.
• Ensure electrical connections are secure and free of corrosion.
• Perform routine maintenance on the vacuum pump.
Sensor Issue
• Do not ignore the brake warning light.
• Have the brake system inspected by a professional if unsure.
• Avoid driving the vehicle if braking performance is severely compromised.
Check if the vehicle's brake system components are covered under warranty.
The C1031 code has been associated with vehicles using electronic brake systems with vacuum assistance.
High – Affects braking performance, which is critical for vehicle safety.
Driving with impaired brakes can lead to accidents and is illegal in many jurisdictions.
• Vehicle at operating temperature
• Engine running
The brake system vacuum sensor is typically located near the brake booster in the engine bay.
Q: Can I drive with a C1031 code?
A: It's not recommended as it can affect braking performance, posing a safety risk.
Q: How can I reset the C1031 code?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
Pro · Four-system diagnostics
A handheld scanner aimed at engine, transmission, ABS, and airbag diagnostic work.
Chassis and ABS faults usually need a scanner that can read brake-system data directly.
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Universal · Torque wrench
Useful when reassembly torque matters for wheel, suspension, and under-hood fasteners.
Useful when wheel, hub, or suspension hardware needs correct reassembly torque.
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Universal · Drive-on ramps
Helpful for safer access underneath the vehicle during exhaust, EVAP, and underbody inspection work.
Helpful for safer access during underbody inspection work.
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