C1101 - FAULT CODE - OBD2

C1101 BUICK, CADILLAC, CHEVROLET, GMC, HUMMER, PONTIAC, SATURN: BRAKE BOOSTER VACUUM SENSOR PERFORMANCE

The Brake Booster Vacuum Sensors are electronic devices installed in vehicles that have vacuum pumps for their brake boosters. These sensors are generally located in the brake booster. They control the amount of vacuum present in the internal part of the brake booster. Besides that, they also regulate how much vacuum is present. Thus, they ensure that the vacuum available is enough for the right performance of the power brakes.

The EBCM (Electronic Brake Control Module) sends 5 volts of the reference voltage to the Brake Boost Vacuum Sensor, this sensor converts the change in vacuum levels into a voltage signal. This signal is sent to the EBCM, which ranges from 0.13 to 3.30 volts depending on the vacuum level. The low reference is the return side of the sensor to the ground.

The C1101 OBD2 fault code is a specific code, which is related to a problem in the Brake Servo Vacuum Sensor in some cases. The code indicates that the Brake Boost Vacuum Sensor is performing erratically, which affects its performance.

• Check Engine lamp ON.
• The light indicating problems in the Anti-Lock Brake System turns on
• The brake pedal remains stiff.

The C1101 OBDII diagnostic code C1101 is stored for the following reasons:

• The Brake servo vacuum sensor wires may be bad.
• The Brake Booster Vacuum Sensor circuit may have damaged electrical connections.
• The brake servo vacuum sensor may be faulty.

To troubleshoot the DTC C1101 OBD2, try this:

• First, consult the TSBs.
• Check all the wires related to the Brake Servo Vacuum Sensor and verify that they are in good condition. If you discover common damage, make the appropriate adjustments.
• Measure the brake servo vacuum sensor circuit voltages and compare these values with those specified by the manufacturer. If the voltages obtained differ from those expected, check for bad connections. Fix if necessary.
• Follow the manufacturer's diagnostic steps and verify the Brake Booster Vacuum Sensor is in good condition. If after performing these tests you determine the sensor does not meet factory requirements, consider replacing it.