DTC P0555-00: Brake Booster Pressure Sensor (running); DTC P0555-2A: Brake Booster Pressure Sensor Signal Stuck In Range [10/2022 - ]: Procedure

1. Read any other DTCs.

   Powertrain > Stop and Start > Trouble Codes 

   Result

   Result	Proceed to
   DTC P0555-00 or P0555-2A is output	A
   DTC P0555-00 or P0555-2A and other DTCs output	B

   HINT: 

   If any DTCs other than P0555-00 or P0555-2A are output, troubleshoot those DTCs first.

Result: 

B 

GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2022 - 11/2023]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2023 - ] 

Result: 

A 

See step  2

1. Start the engine and warm it up.
2. Turn the ignition switch off. (*1)
3. Turn the ignition switch to ON. (engine is stopped) (*2)
4. Depress the brake pedal 5 times and read the changes in the following pressure value. (*3)

   Powertrain > Stop and Start > Data List 

   Tester Display
   Brake Boost Pressure

   OK

   Tester Display	Condition	Normal Condition
   Brake Boost Pressure	Ignition switch ON Brake pedal depressed 5 times	Changes by 20 kPa (150 mmHg, 5.91 in. Hg) or higher

   NOTE:

   Because it is hard to cause variation in the internal pressure before and after depressing the brake pedal if the brake booster internal pressure is high before depressing the brake pedal, do not operate the brake pedal as much as possible between operations (*1) and (*3).

   Result

   Proceed to
   OK
   NG

Result: 

OK 

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

Result: 

NG 

See step  3

1. Check the vacuum hose (brake booster hose) for cracks or clogging (visual check).

   HINT: 

   If the braking force is abnormal, inspect the brake booster assembly.

   OK

   No cracks or clogging in the vacuum hose (brake booster hose).

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE VACUUM HOSE 

Result: 

OK 

See step  4

1. Replace the vacuum sensor assembly.

   Refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  5

1. Clear the DTC.

   Powertrain > Stop and Start > Clear DTCs 

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  6

1. Start the engine and warm it up.
2. Drive the vehicle at 30 km/h (19 mph) or more and stop the vehicle. Repeat this driving pattern 30 times to allow the brake booster vacuum to change.

   Powertrain > Stop and Start > Data List 

   Tester Display
   Brake Boost Pressure

   WARNING:

   When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

3. Stop the vehicle.
4. Check that no DTCs are output.

   Powertrain > Stop and Start > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are not output	A
   DTC P0555-00 or P0555-2A is output	B

Result: 

A 

END 

Result: 

B 

REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [10/2022 - 11/2023]  , or refer to  REMOVAL [11/2023 - ]