DTC C0078-00: Different Diameter Tire [11/2023 - ]: Procedure

1. Check the tire sizes to ensure that the front and rear tire sizes are not different.

   Refer to INSPECTION [12/2019 - ]

   HINT: 

   If different tire sizes are discovered, replace the tires so that the tire sizes are the same on all 4 wheels.

2. Adjust the air pressure in the tires.

   Refer to INSPECTION [12/2019 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  2

1. Clear the DTCs.

   Chassis > Brake/EPB > Clear DTCs 

2. Turn the ignition switch off.
3. Turn the ignition switch to ON (READY).
4. Drive the vehicle at a constant speed of 30 km/h (19 mph) or higher for several minutes.
5. Check if the same DTC is output.

   Chassis > Brake/EPB > Trouble Codes 

6. Check that no electronically controlled brake system speed sensor DTCs are output.

   Chassis > Brake/EPB > Trouble Codes 

   HINT: 

   • If C0078-00 and electronically controlled brake system DTCs are output simultaneously, check and repair the trouble areas in the electronically controlled brake system.
   • When a DTC has been stored, the vehicle condition when the DTC was stored can be determined from the freeze frame data.

     Refer to FREEZE FRAME DATA [11/2023 - ]

   Result

   Result	Proceed to
   DTCs are not output	A
   Electronically controlled brake system speed sensor DTCs are output	B
   Only C0078-00 is output	C

Result: 

A 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ] 

Result: 

B 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS. Refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2023 - ] 

Result: 

C 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2023 - ]