DTC C1427-71: ABS Pump Motor Actuator Stuck [11/2020 - ]: Procedure

1. Check the operating sound of the pump motor when operating it using the GTS.

   Chassis > Brake/EPB > Active Test 

   Tester Display	Measurement Item	Control Range	Restrict Condition	Diagnostic Note
   Motor Relay	ABS motor relay	OFF / ON	Vehicle condition: Vehicle stopped HINT:  To protect this Actuator and Solenoid, this test will only last 5 seconds.	Operating sound of motor can be heard

   Chassis > Brake/EPB > Active Test 

   Tester Display
   Motor Relay

   Result

   Result	Proceed to
   Operating sound is heard.	A
   Operating sound is not heard.	B

Result: 

B 

See step  4

Result: 

A 

See step  2

Pre-procedure1

• None

• Clear the DTCs.

  Chassis > Brake/EPB > Clear DTCs 

  Result

  Proceed to
  NEXT

Post-procedure1

• Turn the ignition switch off.

Result: 

NEXT 

See step  3

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 a speed signal of 20 km/h (12 mph) or more is input to the No. 2 skid control ECU (brake actuator assembly) with the ignition switch turned to ON and the stop light switch assembly off, the ECU performs self-diagnosis of the pump motor circuit.
  • If the normal system code is output (no DTCs are output), slightly jiggle the connectors, wire harness, and fuses of the No. 2 skid control ECU (brake actuator assembly).
  • If any DTCs are output while jiggling a connector or wire harness of the No. 2 skid control ECU (brake actuator assembly), inspect and repair the connector or wire harness.
  • If no DTCs were output when reconfirming DTCs, checking for intermittent problems is necessary because it is suspected that the original DTCs were stored due to the poor connection of a connector terminal.

  Result

  Result	Proceed to
  C1427-71 is not output	A
  C1427-71 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 - ] 

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

• 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.

• Measure the resistance according to the value(s) in the table below.

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  A6-30 (GND2) - Body ground	1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal	Below 1 Ω	Ω

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None

Result: 

OK 

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: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR