DTC C1428: Motor Circuit [04/2018 - 08/2021]: Procedure

1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

   OK

   The connector is securely connected.

2. Disconnect the A28 skid control ECU (brake actuator assembly) connector.
3. Check both the connector case and the terminals for deformation and corrosion.

   OK

   No deformation or corrosion.

4. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A28-1 (+BM) - Body ground	Always	11 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (+BM CIRCUIT) 

Result: 

OK 

See step  2

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A28-14 (GND2) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (GND2 CIRCUIT) 

Result: 

OK 

See step  3

1. Reconnect the A28 skid control ECU (brake actuator assembly) connector.
2. Clear the DTCs.

   Chassis > ABS/VSC/TRAC/EPB > Clear DTCs 

3. Turn the engine switch off.
4. Start the engine.
5. Perform a road test.
6. Check if the same DTC is output.

   Chassis > ABS/VSC/TRAC/EPB > Trouble Codes 

   Result

   Result	Proceed to
   C1428 is not output	A
   C1428 is output	B

Result: 

A 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [04/2018 -] 

Result: 

B 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [04/2018 - 08/2020]  , or refer to  REMOVAL [08/2020 - 08/2021]