Code No. C202A: Pump motor drive long time (Brake electric vacuum pump)
Code No. C202B: Vacuum pressure abnormal loss (Brake electric vacuum pump)
Code No. C202C: Pressure long time low (Brake electric vacuum pump)



caution If there is any problem in the CAN bus lines, an incorrect diagnosis code may be stored. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
note When the diagnosis code is stored under the following conditions, it does indicate a malfunction. Erase the diagnosis code and then complete the check.

  • Code No. C202A, C202B, C202C: Bleeding is carried out with the system activated (READY (ready to drive) illuminates and the power supply mode of the electric motor switch is at ACC).
  • C202B: The brake pedal is depressed gently to maintain a vehicle speed of approx. 6 km/h or less.

TROUBLE JUDGEMENT


The PHEV-ECU stores the diagnosis codes below when the brake vacuum pressure system fails.
Code No.C202A
  • The brake electric vacuum pump motor is energised for a certain period or more with the brake pedal not depressed.
Code No.C202B
  • The brake vacuum decreases by a certain amount with the brake pedal not depressed.
Code No.C202C
  • The brake vacuum decreases for a certain period (this diagnosis code is stored when the vacuum warning buzzer sounds for a certain period).

PROBABLE CAUSES



  • Malfunction of vacuum line
  • Malfunction of check valve
  • Malfunction of brake booster
  • Malfunction of brake electric vacuum pump
  • Malfunction of the brake electric vacuum pump relay box
  • Malfunction of brake booster vacuum sensor

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III CAN bus diagnostics


Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?

Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting ). On completion, go to Step 2.

STEP 2. Check whether the diagnosis code is stored again.


Recheck if the diagnosis code is stored.
(1)Erase the diagnosis code.
(2)Turn on the power supply mode of the electric motor switch.
(3)Check if the diagnosis code is stored.

Q. Is the diagnosis code stored?

Go to Step 3.
The procedure is complete.

STEP 3. M.U.T.-III other system diagnosis code


Check whether another diagnosis code, which is related to the brake vacuum generating system, is stored. (Refer to ).

Q. Is the diagnosis code stored?

Troubleshoot for the relevant diagnosis code.
Go to Step 4.

STEP 4. M.U.T.-III data list (ASC-ECU)


Check that the following data list display contents are normal. (Refer to GROUP 35C- Data list reference table ).
Data list
  • Item 10: Master cylinder pressure (+: pressure increase, -: pressure decrease)
Check condition
Normal condition
The brake pedal is depressed.
Increases by the amount of the brake pedal depression.
The brake pedal is released.
-3 to 3 bar

  • Item 91: Brake pressure sensor
Check condition
Normal condition
The brake pedal is depressed.
ON
The brake pedal is released.
OFF

Q. Is the check result normal?

Go to Step 7.
Go to Step 5.

STEP 5. Brake vacuum line check


Refer to GROUP 35A - On-vehicle Service - Brake Vacuum Line Check .

Q. Is the check result normal?

Go to Step 6.
Repair it.

STEP 6. Electric brake vacuum pump check


Refer to GROUP 35A - On vehicle Service - Brake electric vacuum pump check .

Q. Is the check result normal?

Go to Step 7.
Replace the brake electric vacuum pump. (Refer to GROUP 35A - Brake Electric Vacuum Pump .)

STEP 7. Check whether the diagnosis code is stored again.


Recheck if the diagnosis code is stored.
(1)Erase the diagnosis code.
(2)Turn on the power supply mode of the electric motor switch.
(3)Check if the diagnosis code is stored.

Q. Is the diagnosis code stored?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
The procedure is complete.