DESCRIPTION The skid
control ECU (brake actuator assembly) receives signals from the yaw rate
and acceleration sensor (airbag sensor assembly) via CAN communication. HINT:
If
there is a malfunction in the bus lines between the yaw rate and
acceleration sensor (airbag sensor assembly) and the CAN communication
system, DTC U0123 (Lost Communication With Yaw Rate Sensor Module) is
output. When U0123 is output together with C1234, C1472 and/or C1474,
inspect and repair the trouble areas indicated by U0123 first. These DTCs may be stored if one of the following occurs:
- Yaw rate and acceleration sensor circuit malfunction.
- Yaw rate and acceleration sensor (airbag sensor assembly) installation abnormality.
- Yaw rate and acceleration sensor signal malfunction.
|
DTC No. | Detection Item |
DTC Detection Condition | Trouble Area | |
C1234 | Yaw Rate Sensor |
Any of the following is detected:
- The yaw rate sensor offset value is estimated as less than -5.25 deg/s
or more than 5.25 deg/s based on offset correction performed when the
vehicle is stopped and then the vehicle starts off.
- The offset correction did not complete with the vehicle stopped, and the
yaw rate sensor offset value is estimated as less than -15 deg/s or
more than 15 deg/s based on the offset correction performed while the
vehicle is being driven.
- The offset correction completed with the vehicle stopped and the yaw
rate sensor offset value is less than -7.5 deg/s or more than 7.5 deg/s.
- The yaw rate sensor offset value is estimated as less than -7.5 deg/s or
more than 7.5 deg/s based on the offset correction performed while the
vehicle is being driven.
- After the VSC system has turned on, but before the vehicle starts off,
the yaw rate sensor value is less than -30 deg/s or more than 30 deg/s
for 5 seconds or more when the vehicle is stopped.
- After the VSC system has turned on, but before the vehicle starts off,
the yaw rate sensor value is less than -30 deg/s or more than 30 deg/s
for 0.5 seconds or more when the vehicle starts off.
- After the VSC system has turned on, but before the vehicle starts off,
as the vehicle starts off, the yaw rate sensor value is less than -30
deg/s or more than 30 deg/s for 0.5 seconds or more.
- The yaw rate sensor value is less than -94.75 deg/s or more than 94.75 deg/s for 0.8 seconds or more.
- The change of the yaw rate sensor value within 0.04 seconds is abnormal.
- The value from the yaw rate sensor is judged as abnormal based on the skid control ECU (brake actuator assembly) estimation.
|
- Yaw rate sensor (airbag sensor assembly) installation
- Yaw rate sensor (airbag sensor assembly)
- Yaw rate sensor circuit
| | C1472 |
Deceleration Sensor | Any of the following is detected:
- With the vehicle stopped, the internal acceleration value is less than -7 m/s2 or more than 7 m/s2 for 0.4 seconds or more.
- The acceleration sensor offset value is estimated as less than -2.25
m/s2 or more than 2.25 m/s2 based on the offset correction performed
while the vehicle is being driven.
- The acceleration sensor value is less than -14.6 m/s2 or more than 14.6 m/s2 for 0.8 seconds or more.
|
- Acceleration sensor (airbag sensor assembly) installation
- Acceleration sensor (airbag sensor assembly)
- Acceleration sensor circuit
| | C1474 |
Forward and Rearward G Sensor |
Any of the following is detected:
- The acceleration sensor offset value is estimated as less than -2.25
m/s2 or more than 2.25 m/s2 based on the offset correction performed
while the vehicle is being driven.
- The acceleration sensor value is less than -14.6 m/s2 or more than 14.6 m/s2 for 3 seconds or more.
|
- Acceleration sensor (airbag sensor assembly) installation
- Acceleration sensor (airbag sensor assembly)
- Acceleration sensor circuit
| DTC Detection Conditions: C1234 | |
Vehicle Condition | |
Pattern 1 | Pattern 2 |
Pattern 3 | Pattern 4 |
Pattern 5 | |
Diagnosis Condition | The offset correction did not complete with the vehicle stopped. |
- | ○ |
- | - |
- | | The offset correction completed with the vehicle stopped. |
- | - |
○ | - |
- | | The vehicle is being driven. |
- | - |
- | ○ |
- | | The VSC system has turned on, but the vehicle has not started off. |
- | - |
- | - |
○ | |
Malfunction Status | The
yaw rate sensor offset value is estimated as less than -5.25 deg/s or
more than 5.25 deg/s based on offset correction performed when the
vehicle is stopped and then the vehicle starts off. |
○ | - |
- | - |
- | | The
yaw rate sensor offset value is estimated as less than -15 deg/s or
more than 15 deg/s based on the offset correction performed while the
vehicle is being driven. | - |
○ | - |
- | - | |
The yaw rate sensor offset value is less than -7.5 deg/s or more than 7.5 deg/s. |
- | - |
○ | - |
- | | The
yaw rate sensor offset value is estimated as less than -7.5 deg/s or
more than 7.5 deg/s based on the offset correction performed. |
- | - |
- | ○ |
- | | The yaw rate sensor value is less than -30 deg/s or more than 30 deg/s. |
- | - |
- | - |
○ | |
Detection Time | - |
- | - |
- | 5 seconds or more when the vehicle is stopped. | |
Number of Trips | 1 trip |
1 trip | 1 trip |
1 trip | 1 trip |
HINT: DTC will be output when conditions for either of the patterns in the table above are met. DTC Detection Conditions: C1234 | |
Vehicle Condition | |
Pattern 6 | Pattern 7 |
Pattern 8 | Pattern 9 |
Pattern 10 | |
Diagnosis Condition | The VSC system has turned on, but the vehicle has not started off. |
○ | ○ |
- | - |
- | |
Malfunction Status | The yaw rate sensor value is less than -30 deg/s or more than 30 deg/s. |
○ | - |
- | - |
- | | As the vehicle starts off, the yaw rate sensor value is less than -30 deg/s or more than 30 deg/s. |
- | ○ |
- | - |
- | | The yaw rate sensor value is less than -94.75 deg/s or more than 94.75 deg/s. |
- | - |
○ | - |
- | | The change of the yaw rate sensor value within 0.04 seconds is abnormal. |
- | - |
- | ○ |
- | | The value from the yaw rate sensor is judged as abnormal based on the skid control ECU (brake actuator assembly) estimation. |
- | - |
- | - |
○ | |
Detection Time | 0.5 seconds or more when the vehicle starts off. |
0.5 seconds or more | 0.8 seconds or more |
- | - | |
Number of Trips | 1 trip |
1 trip | 1 trip |
1 trip | 1 trip |
HINT: DTC will be output when conditions for either of the patterns in the table above are met. DTC Detection Conditions: C1472 | |
Vehicle Condition | |
Pattern 1 | Pattern 2 |
Pattern 3 | |
Diagnosis Condition | The vehicle stopped. |
○ | - |
- | | Vehicle is being driven. |
- | ○ |
- | |
Malfunction Status | The internal acceleration value is less than -7 m/s2 or more than 7 m/s2. |
○ | - |
- | | The
acceleration sensor offset value is estimated as less than -2.25 m/s2
or more than 2.25 m/s2 based on the offset correction performed. |
- | ○ |
- | | The acceleration sensor value is less than -14.6 m/s2 or more than 14.6 m/s2. |
- | - |
○ | |
Detection Time | 0.4 seconds or more |
- | 0.8 seconds or more | |
Number of Trips | 1 trip |
1 trip | 1 trip |
HINT: DTC will be output when conditions for either of the patterns in the table above are met. DTC Detection Conditions: C1474 | |
Vehicle Condition | |
Pattern 1 | Pattern 2 | |
Diagnosis Condition | The vehicle is being driven. |
○ | - | |
Malfunction Status | The
acceleration sensor offset value is estimated as less than -2.25 m/s2
or more than 2.25 m/s2 based on the offset correction performed. |
○ | - | |
The acceleration sensor value is less than -14.6 m/s2 or more than 14.6 m/s2. |
- | ○ | |
Detection Time | - |
3 seconds or more | |
Number of Trips | 1 trip |
1 trip | HINT: DTC will be output when conditions for either of the patterns in the table above are met. WIRING DIAGRAM
 CAUTION / NOTICE / HINT
NOTICE:
- Inspect the fuses for circuits related to this system before performing the following procedure.
- After replacing or reinstalling the yaw rate and acceleration sensor
(airbag sensor assembly), perform system variant learning and
acceleration sensor zero point calibration.
Click here 
HINT: When
U0123 and/or U0126 is output together with C1234, C1472 and/or C1474,
inspect and repair the trouble areas indicated by U0123 and/or U0126
first. Click here PROCEDURE
(a) Clear the DTCs. Chassis > ABS/VSC/TRAC/EPB > Clear DTCs
(b) Turn the engine switch off. (c) Start the engine. (d)
At a speed of 30 km/h (18 mph) or more, drive the vehicle, turn the
steering wheel, and decelerate (depress the brake pedal) the vehicle. (e) Turn the engine switch off.
(f) Turn the engine switch on (IG) again and check that no CAN communication system DTCs are output.
Click here
|
Result | Proceed to | |
CAN communication system DTCs are not output |
A | | CAN communication system DTCs are output |
B |
| B |
 | INSPECT CAN COMMUNICATION SYSTEM |
|
A |
 | |
| 2. |
CHECK AIRBAG SENSOR ASSEMBLY INSTALLATION |
(a) Turn the engine switch off. (b) Check that the yaw rate and acceleration sensor (airbag sensor assembly) has been installed properly.
Click here OK: The yaw rate and acceleration sensor (airbag sensor assembly) is tightened to the specified torque.
The yaw rate and acceleration sensor (airbag sensor assembly) is not installed in a tilted position.
| NG |
| INSTALL AIRBAG SENSOR ASSEMBLY CORRECTLY |
|
OK | |
| |
| 3. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) |
| (a) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK: The connector is securely connected. |
 |
|
*a | Front view of wire harness connector
(to Yaw Rate and Acceleration Sensor (Airbag Sensor Assembly)) | | |
(b) Disconnect the G50 yaw rate and acceleration sensor (airbag sensor assembly) connector.
(c) Check both the connector case and the terminals for deformation and corrosion.
OK: No deformation or corrosion. (d) Turn the engine switch on (IG).
(e) Measure the voltage according to the value(s) in the table below. Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
G50-36 (IG2) - Body ground |
Engine switch on (IG) |
11 to 14 V |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) |
|
OK | |
| |
| 4. |
CHECK HARNESS AND CONNECTOR (GROUND TERMINAL) |
| (a) Turn the engine switch off. |
 |
|
*a | Front view of wire harness connector
(to Yaw Rate and Acceleration Sensor (Airbag Sensor Assembly)) | | |
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
G50-33 (E1) - Body ground |
Always | Below 1 Ω | |
G50-32 (E2) - Body ground |
Always | Below 1 Ω |
| OK |
| REPLACE AIRBAG SENSOR ASSEMBLY |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT) | | 
