DTC C13DB-00: Brake Pressure Too Low (Brake M/C1); DTC C13DD-00: Brake Pressure Too Low (Brake M/C2) [11/2020 - ]: Procedure
- CUSTOMER PROBLEM ANALYSIS (CHECK CONDITION WHEN MALFUNCTION OCCURRED) AND FREEZE FRAME DATA
- Interview the customer to check the vehicle conditions when the brake system warning light (yellow indicator) illuminated.
- Using the GTS, check for Freeze Frame Data that is recorded when a DTC is stored.
Chassis > Brake/EPB > Trouble Codes
HINT:
Freeze Frame Data is only stored once when a DTC is stored.
Result
Proceed to NEXT
Result:
NEXT
See step 2
- CLEAR DTC
Pre-procedure1
- None
- Clear the DTCs.
Chassis > Brake Booster > Clear DTCs
Chassis > Brake/EPB > Clear DTCs
Result
Proceed to NEXT
Post-procedure1
- Turn the ignition switch off.
Result:
NEXT
See step 3
- CHECK DTC
Pre-procedure1
- Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.
- Check if the same DTC is output.
Chassis > Brake/EPB > Trouble Codes
Result
Result Proceed to Only C13DB-00 or C13DD-00 is output A C13DB-00 or C13DD-00 and other DTCs are output B
Post-procedure1
- None
Result:
B
REPAIR CIRCUITS INDICATED BY OUTPUT DTCS. Refer to DIAGNOSTIC TROUBLE CODE CHART [11/2020 - 12/2022] , or refer to DIAGNOSTIC TROUBLE CODE CHART [12/2022 - 12/2023] , or refer to DIAGNOSTIC TROUBLE CODE CHART [12/2023 - ]
Result:
A
See step 4
- CHECK DTC
- Check if the same DTC is output.
Chassis > Brake Booster > Trouble Codes
Result
Result Proceed to DTCs are not output A DTCs are output B
Result:
B
REPAIR CIRCUITS INDICATED BY OUTPUT DTCS. Refer to DIAGNOSTIC TROUBLE CODE CHART [11/2020 - 12/2022] , or refer to DIAGNOSTIC TROUBLE CODE CHART [12/2022 - 12/2023] , or refer to DIAGNOSTIC TROUBLE CODE CHART [12/2023 - ]
Result:
A
See step 5
- Check if the same DTC is output.
- CHECK FOR FLUID LEAK
- Based on the Freeze Frame Data or interview with the customer, inspect the following items for brake fluid leaks:
- The brake lines from the brake booster with master cylinder assembly to each wheel cylinder.
- The main body of the brake booster with master cylinder assembly and brake actuator assembly.
OK
There are no fluid leaks.
Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE APPLICABLE PART
Result:
OK
See step 6
- Based on the Freeze Frame Data or interview with the customer, inspect the following items for brake fluid leaks:
- CHECK BRAKE DISC
Pre-procedure1
- Turn the ignition switch off.
- Disconnect the A2 brake pedal stroke sensor assembly connector.
- Perform a road test according to Freeze Frame Data or customer problem analysis. While driving, check for abnormal brake pedal vibration caused by brake discs that are worn or have excess runout.
OK
Brake pedal does not vibrate during braking.
HINT:
- An unevenly worn disc may vibrate the caliper piston and cause fluctuations in brake line pressure, triggering a malfunction detection condition.
- The brake pedal does not kick back due to caliper piston vibration during electronically controlled brake system control.
- If the brake pedal stroke sensor assembly connector is disconnected, the fail-safe function will prohibit electronically controlled brake system control.
- Uneven disc wear can be checked by measuring the disc thickness variation.
For Front Brake: Refer to INSPECTION [11/2020 - ]
For Rear Brake: Refer to INSPECTION [11/2020 - ]
Result
Proceed to OK NG
Post-procedure1
- None
Result:
NG
REPLACE BRAKE DISC
Result:
OK
See step 7
- CLEAR DTC
Pre-procedure1
- None
- Clear the DTCs.
Chassis > Brake Booster > Clear DTCs
Chassis > Brake/EPB > Clear DTCs
Result
Proceed to NEXT
Post-procedure1
- Turn the ignition switch off.
Result:
NEXT
See step 8
- PERFORM AIR BLEEDING
HINT:
Refer to BLEEDING [11/2020 - ]
Result
Proceed to NEXT Result:
NEXT
See step 9
- CHECK BRAKE ACTUATOR ASSEMBLY (ACTUATOR SIDE)
Pre-procedure1
- Turn the ignition switch off.
- Make sure that there is no looseness at the locking part and the connecting part of the connectors.
OK
The connector is securely connected.
Pre-procedure2
- After 3 minutes elapse after turning the ignition switch off, disconnect the A6 No. 2 skid control ECU (brake actuator assembly) connector.
- Check both the connector case and the terminals for deformation and corrosion.
OK
No deformation or corrosion.
Result
Proceed to OK NG
Post-procedure1
- None
Result:
NG
REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to REMOVAL [11/2020 - 11/2021] , or refer to REMOVAL [11/2021 - 12/2022] , or refer to REMOVAL [12/2022 - 12/2023] , or refer to REMOVAL [12/2023 - ]
Result:
OK
See step 10
- CHECK HARNESS AND CONNECTOR (VEHICLE SIDE)
Pre-procedure1
- Reconnect the A6 No. 2 skid control ECU (brake actuator assembly) connector.
- Measure the voltage and resistance on the wire harness side.
HINT:
Refer to TERMINALS OF ECU [11/2020 - 12/2023] , or refer to TERMINALS OF ECU [12/2023 - ]
OK
Voltage and resistance readings are all normal.
Result
Proceed to OK NG
Post-procedure1
- None
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 11
- CLEAR DTC
Pre-procedure1
- None
Post-procedure1
- Turn the ignition switch off.
Result:
NEXT
See step 12
- RECONFIRM DTC
Pre-procedure1
- Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.
- Check if the same DTC is output.
Chassis > Brake/EPB > Trouble Codes
HINT:
If the system returns to normal, it is suspected that a DTC was stored due to a poor connection of a terminal in a connector, air in the system, etc.
Result
Result Proceed to C13DB-00 and C13DD-00 are not output A C13DB-00 or C13DD-00 is output B
Post-procedure1
- None
Result:
A
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2020 - ]
Result:
B
REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to REMOVAL [11/2020 - 11/2021] , or refer to REMOVAL [11/2021 - 12/2022] , or refer to REMOVAL [12/2022 - 12/2023] , or refer to REMOVAL [12/2023 - ]