RX400h · Service Manual BRAKE

C1246/46

Diagnostic trouble codes

DESCRIPTION

The master cylinder pressure sensor and the wheel cylinder pressure sensor, which are built into the brake actuator, measure the master cylinder pressure and the wheel cylinder pressure and send to the skid control ECU.
DTC C1281/81 can be deleted when the master cylinder pressure sensor sends a master cylinder pressure signal or the Test Mode ends. DTC C1281/81 is output only in the Test Mode.
DTC No.
 INF Code
 DTC Detecting Condition
 Trouble Area
C1246/46
 191
 Sensor power source 1 (VCM1) voltage is less than 4.7 V or 5.3 V or more for at least 0.05 sec.
  1. Master cylinder pressure sensor
  2. Master cylinder pressure sensor circuit
  3. Master cylinder pressure sensor power supply
  4. Brake actuator assembly
  5. Skid control ECU
C1246/46
 192
 Ratio of master pressure sensor output voltage 1 (PMC1) to sensor power source (VCM1) is less than 5% or 90.5% or more for at least 0.05 sec.
  1. Master cylinder pressure sensor
  2. Master cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1246/46
 194
 Sensor power source 2 (VCM2) voltage is less than 4.7 V or 5.3 V or more for at least 0.05 sec.
  1. Master cylinder pressure sensor
  2. Master cylinder pressure sensor circuit
  3. Master cylinder pressure sensor power supply
  4. Brake actuator assembly
  5. Skid control ECU
C1246/46
 195
 Ratio of master pressure sensor output voltage 2 (PMC2) to sensor power source (VCM2) is less than 5% or 90.5% or more for at least 0.05 sec.
  1. Master cylinder pressure sensor
  2. Master cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1246/46
 197
 Master pressure sensor output voltage 1 (PMC1) is abnormal.
  1. Brake actuator assembly
  2. Skid control ECU
C1246/46
 198
 Master pressure sensor output voltage 2 (PMC2) is abnormal.
  1. Brake actuator assembly
  2. Skid control ECU
C1246/46
 199
 Master pressure sensor output 1 (PMC1) is not approx. 0 Mpa when not braking.
  1. Master cylinder pressure sensor
  2. Master cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1246/46
 200
 Master pressure sensor output 2 (PMC2) is not approx. 0 Mpa when not braking.
  1. Master cylinder pressure sensor
  2. Master cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1246/46
 201
 PMC1 and PMC2 voltages are different when braking.
  1. Master cylinder pressure sensor
  2. Master cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1246/46
 202
 Master pressure sensor 1 data (PMC1) is invalid.
  1. Master cylinder pressure sensor
  2. Brake actuator assembly
  3. Skid control ECU
C1246/46
 205
 Master pressure sensor 2 data (PMC2) is invalid.
  1. Master cylinder pressure sensor
  2. Brake actuator assembly
  3. Skid control ECU
C1364/61
 221
 Sensor power source 1 (VCM1) voltage is less than 4.7 V or 5.3 V or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor power supply
  2. Brake actuator assembly
  3. Skid control ECU
C1364/61
 222
 Raio of FR right sensor output voltage (PFR) to sensor power source (VCM1) is less than 5% or 90.5% or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 224
  1. FR right sensor output (PFR) is not approx. 0 Mpa when not braking.
  2. FR right sensor (PFR) zero point malfunction.
  3. Open or short in FR right sensor (PFR) circuit.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 225
 Ratio of FR right sensor output voltage (PFR) to sensor power source (VCM1) is less than 90.5% for at least 0.1 sec. when self-diagnosis signal is output.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 227
 Sensor power source 2 (VCM2) voltage is less than 4.7 V or 5.3 V or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor power supply
  2. Brake actuator assembly
  3. Skid control ECU
C1364/61
 228
 Ratio of FR left sensor output voltage (PFL) to sensor power source (VCM2) is less than 5% or 90.5% or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 230
  1. FR left sensor (PFL) is not approx. 0 Mpa when not braking.
  2. FR left sensor (PFL) zero point malfunction.
  3. Open or short in FR right sensor (PFL) circuit.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 231
 Ratio of FR left sensor output voltage (PFL) to sensor power source (VCM2) is less than 90.5% for at least 0.1 sec. when self-diagnosis signal is output.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 233
 Sensor power source 2 (VCM2) voltage is less than 4.7 V or 5.3 V or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor power supply
  2. Brake actuator assembly
  3. Skid control ECU
C1364/61
 234
 Ratio of RR right sensor output voltage (PRR) to sensor power source (VCM2) is less than 5% or 90.5% or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 236
  1. RR right sensor output voltage (PRR) is not approx. 0 Mpa when not braking.
  2. RR right sensor (PRR) zero point malfunction.
  3. Open or short in RR sensor (PRR) circuit.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 237
 Ratio of RR right sensor output voltage (PRR) to sensor power source (VCM2) is less than 90.5% for at least 0.1 sec. when self-diagnosis signal is output.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 239
 Sensor power source (VCM1) voltage is less than 4.7 V or 5.3 V or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor power supply
  2. Brake actuator assembly
  3. Skid control ECU
C1364/61
 240
 Ratio of RR left sensor output voltage (PRL) to sensor power source (VCM1) is less than 5% or 90.5% or more for at least 0.05 sec.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 242
  1. RR left sensor output (PRL) is not approx. 0 Mpa when not braking.
  2. RR left sensor (PRL) zero point malfunction.
  3. Open or short in RR left sensor (PRL) circuit.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU
C1364/61
 243
 Ratio of RR left sensor output voltage (PRL) to sensor power source (VCM1) is less than 90.5% for at least 0.1 sec. when sel-diagnosis signal is output.
  1. Wheel cylinder pressure sensor
  2. Wheel cylinder pressure sensor circuit
  3. Brake actuator assembly
  4. Skid control ECU

WIRING DIAGRAM

F047299E04

INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (Click here).


1. CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND BRAKE ACTUATOR ASSEMBLY)

  1. F047487E03
    Disconnect the skid control ECU connector and brake actuator connector.

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

    Resistance:
    Tester Connection
    		 Specified Condition
    S41-8 (E) - B18-14 (E1)
    		 Below 1 Ω
    S41-9 (VCM) - B18-10 (VCM1)
    		 Below 1 Ω
    S41-18 (PRL) - B18-11 (PRL)
    		 Below 1 Ω
    S41-21 (PAC1) - B18-15 (PACC)
    		 Below 1 Ω
    S41-23 (PFR) - B18-9 (PFR)
    		 Below 1 Ω
    S41-30 (PMC1) - B18-13 (PMC1)
    		 Below 1 Ω
    S41-31 (PCK1) - B18-12 (PCK1)
    		 Below 1 Ω
    S38-14 (VCM2) - B18-5 (VCM2)
    		 Below 1 Ω
    S38-21 (PCK2) - B18-7 (PCK2)
    		 Below 1 Ω
    S38-23 (PFL) - B18-4 (PFL)
    		 Below 1 Ω
    S38-27 (PMC2) - B18-8 (PMC2)
    		 Below 1 Ω
    S38-29 (E2) - B18-16 (E2)
    		 Below 1 Ω
    S38-31 (PRR) - B18-6 (PRR)
    		 Below 1 Ω

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

    Resistance:
    Tester Connection
    		 Specified Condition
    S41-8 (E) - Body ground
    		 10 kΩ or higher
    S41-9 (VCM) - Body ground
    		 10 kΩ or higher
    S41-18 (PRL) - Body ground
    		 10 kΩ or higher
    S41-21 (PAC1) - Body ground
    		 10 kΩ or higher
    S41-23 (PFR) - Body ground
    		 10 kΩ or higher
    S41-30 (PCM1) - Body ground
    		 10 kΩ or higher
    S41-31 (PCK1) - Body ground
    		 10 kΩ or higher
    S38-14 (VCM2) - Body ground
    		 10 kΩ or higher
    S38-21 (PCK2) - Body ground
    		 10 kΩ or higher
    S38-27 (PMC2) - Body ground
    		 10 kΩ or higher
    S38-29 (E2) - Body ground
    		 10 kΩ or higher
    S38-31 (PRR) - Body ground
    		 10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2. INSPECT SKID CONTROL ECU
F047485E20

  1. Connect the skid control ECU connector.

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

    HINT:
    Measure the voltage from the back side of the connector with the connector connected to the skid control ECU.

    Voltage:
    Tester Connection
    		 Condition
    		 Specified Condition
    S41-9 (VCM) - Body ground
    		 Ignition switch ON
    		 4.75 to 5.25 V
    S38-14 (VCM2) - Body ground
    		 Ignition switch ON
    		 4.75 to 5.25 V

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

    Resistance:
    Tester Connection
    		Specified Condition
    S41-8 (E) - Body ground
    		 Below 1 Ω
    S38-29 (E2) - Body ground
    		 Below 1 Ω



NG
REPLACE SKID CONTROL ECU
OK


3. READ VALUE OF INTELLIGENT TESTER (MASTER CYLINDER PRESSURE SENSOR)

  1. Connect the intelligent tester to the DLC3.

  1. Select the DATA LIST mode on the intelligent tester.

    ABS / VSC / TRAC: 
    Item
    		 Measurement Item /
    Range (Display)
    		 Normal Condition
    Master Cylinder Sensor
    		 Master cylinder pressure sensor 1 reading /
    min.: 0 V, max.: 5 V
    		 When brake pedal is released:
    0.3 to 0.9 V
    Master Cylinder Sensor 2
    		 Master cylinder pressure sensor 2 reading /
    min.: 0 V, max.: 5 V
    		 When brake pedal is released:
    0.3 to 0.9 V

  1. Check the output value of the master cylinder pressure sensor on the intelligent tester display.

    OK:
    When the pedal is depressed, displayed voltage on the intelligent tester increases.



 NG
REPLACE BRAKE ACTUATOR ASSEMBLY
OK


4. READ VALUE OF INTELLIGENT TESTER (WHEEL CYLINDER PRESSURE SENSOR)

  1. Connect the pedal effort gauge.

  1. Install the LSPV gauge (SST) and bleed air (Click here).

SST
09709-29018  

  1. Connect the intelligent tester to the DLC3.

  1. Select the DATA LIST mode on the intelligent tester.

    ABS / VSC / TRAC: 
    Item
    		 Measurement Item /
    Range (Display)
    		 Normal Condition
    FR W/C Sensor
    		 Front Right pressure sensor /
    min.: 0 V, max.: 5 V
    		 When brake pedal is released:
    0.3 to 0.9 V
    FL W/C Sensor
    		 Front Left pressure sensor /
    min. 0 V, max.: 5 V
    		 When brake pedal is released:
    0.3 to 0.9 V
    RR W/C Sensor
    		 Rear Right pressure sensor /
    min.: 0 V, max.: 5 V
    		 When brake pedal is released:
    0.3 to 0.9 V
    RL W/C Sensor
    		 Rear Left pressure sensor /
    min. 0 V, max.: 5 V
    		 When brake pedal is released:
    0.3 to 0.9 V

  1. Check the output value of the wheel cylinder pressure sensor at each fluid pressure during the ECB control.

    Voltage:
    Front wheel cylinder pressure sensor 
    Fluid Pressure
    MPa (kgf/cm2, psi)
    		 FR PRESS SENS
    (DATA-LIST)
    		 FL PRESS SENS
    (DATA-LIST)
    2.6 (26.5, 376.9)
    		 0.85 to 1.15 V
    		 0.85 to 1.15 V
    6.3 (64.3, 914.5)
    		 1.6 to 1.9 V
    		 1.6 to 1.9 V
    8.1 (82.6, 1174.8)
    		 1.95 to 2.25 V
    		 1.95 to 2.25 V
    8.2 (83.6, 1189.0)
    		 2.0 to 2.3 V
    		 2.0 to 2.3 V
    Rear wheel cylinder pressure sensor 
    Fluid Pressure
    MPa (kgf/cm2, psi)
    		 RR PRESS SENS
    (DATA-LIST)
    		 RL PRESS SENS
    (DATA-LIST)
    2.7 (27.5, 391.1)
    		 0.85 to 1.15 V
    		 0.85 to 1.15 V
    5.0 (51.0, 725.4)
    		 1.35 to 1.65 V
    		 1.35 to 1.65 V



NG
REPLACE BRAKE ACTUATOR ASSEMBLY
OK

REPLACE SKID CONTROL ECU


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