DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)
READ VALUE USING GTS (FR/FL WHEEL SPEED)
RECONFIRM DTC
INSPECT SKID CONTROL SENSOR WIRE
CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)
CHECK HARNESS AND CONNECTOR (FR+/FL+ TERMINAL)
DTC C1405 Open or Short in Front Speed Sensor RH Circuit
DTC C1406 Open or Short in Front Speed Sensor LH Circuit
DESCRIPTION
Refer to DTCs C1401 and C1402 ().
| DTC Code | DTC Detection Condition | Trouble Area |
C1405
C1406 | Either condition is met:
An open in the speed sensor signal circuit continues for 0.5 seconds or more.
With the IG1 terminal voltage at 9.5 V or higher, the sensor power supply voltage decreases for 0.5 seconds or more.
| Front speed sensor RH/LH
Skid control sensor wire
Speed sensor circuit
Skid control ECU (Master cylinder solenoid)
|
DTC C1405 is for the front speed sensor RH.
DTC C1406 is for the front speed sensor LH.
WIRING DIAGRAM
INSPECTION PROCEDURE
After replacing the master cylinder solenoid, perform zero point calibration and store the system information ().
Check the speed sensor signal after replacement ().
| 1.CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION) |
Using the GTS, check for any momentary interruption in the wire harness and connector corresponding to the DTC ().
ABS/VSC/TRC| Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
| FR Speed Open | Front speed sensor RH open circuit detection/ Error or Normal | Normal | - |
| FL Speed Open | Front speed sensor LH open circuit detection/ Error or Normal | Normal | - |
- OK:
- Normal (there are no momentary interruptions).
- Perform the above inspection before removing the sensor and connector.
| 2.READ VALUE USING GTS (FR/FL WHEEL SPEED)
|
Turn the ignition switch off.
Connect the GTS to the DLC3.
Enter the following menus: Chassis / ABS/VSC/TRC / Data List.
ABS/VSC/TRC| Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
| FR Wheel Speed | Front speed sensor RH reading/ Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph) | Actual wheel speed | No large fluctuations when driving at a constant speed. |
| FL Wheel Speed | Front speed sensor LH reading/ Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph) | Actual wheel speed | No large fluctuations when driving at a constant speed. |
Check that there is no difference between the speed value output from the speed sensor displayed on the GTS and the speed value displayed on the speedometer when driving the vehicle.
- Factors that affect the indicated vehicle speed include tire size, tire inflation and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using a speedometer tester (calibrated chassis dynamometer). For details about testing and the margin of error, refer to the reference chart ().
- OK:
- The speed value output from the speed sensor displayed on the GTS is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).
Turn the ignition switch off.
Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.
Check if the same DTC is output ().
Result| Result | Proceed to |
| DTC is not output | A |
| DTC is output (for LHD) | B |
| DTC is output (for RHD) | C |
| | REPLACE MASTER CYLINDER SOLENOID ()
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| | REPLACE MASTER CYLINDER SOLENOID ()
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| A | |
| |
| CHECK FOR INTERMITTENT PROBLEMS ()
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| 4.INSPECT SKID CONTROL SENSOR WIRE |
Remove the skid control sensor wire ().
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
for RH| Tester Connection | Condition | Specified Condition |
| Az2-1 - z17-1 (FR-) | Always | Below 1 Ω |
| Az2-5 - z17-2 (FR+) | Always | Below 1 Ω |
| z17-1 (FR-) - z17-2 (FR+) | Always | 10 kΩ or higher |
for LH| Tester Connection | Condition | Specified Condition |
| Az1-1 - z18-1 (FL-) | Always | Below 1 Ω |
| Az1-5 - z18-2 (FL+) | Always | Below 1 Ω |
| z18-1 (FL-) - z18-2 (FL+) | Always | 10 kΩ or higher |
Text in Illustration| *A | for RH |
| *B | for LH |
| *1 | Skid Control Sensor Wire |
| | REPLACE SKID CONTROL SENSOR WIRE ()
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| 5.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR) |
Install the skid control sensor wire ().
Disconnect the A24 skid control ECU (master cylinder solenoid) connector.
Disconnect the z17 and/or z18 speed sensor connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
for RH| Tester Connection | Condition | Specified Condition |
| A24-3 (FR+) - z17-2 (FR+) | Always | Below 1 Ω |
| A24-3 (FR+) - Body ground | Always | 10 kΩ or higher |
| A24-17 (FR-) - z17-1 (FR-) | Always | Below 1 Ω |
| A24-17 (FR-) - Body ground | Always | 10 kΩ or higher |
for LH| Tester Connection | Condition | Specified Condition |
| A24-18 (FL+) - z18-2 (FL+) | Always | Below 1 Ω |
| A24-18 (FL+) - Body ground | Always | 10 kΩ or higher |
| A24-4 (FL-) - z18-1 (FL-) | Always | Below 1 Ω |
| A24-4 (FL-) - Body ground | Always | 10 kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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| 6.CHECK HARNESS AND CONNECTOR (FR+/FL+ TERMINAL) |
Disconnect the speed sensor connector.
Connect the A24 skid control ECU (master cylinder solenoid) connector.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
for RH| Tester Connection | Switch Condition | Specified Condition |
| z17-2 (FR+) - Body ground | Ignition switch ON | 11 to 14 V |
for LH| Tester Connection | Switch Condition | Specified Condition |
| z18-2 (FL+) - Body ground | Ignition switch ON | 11 to 14 V |
Text in Illustration| *A | for RH |
| *B | for LH |
| *a | Front view of wire harness connector
(to Front Speed Sensor) |
Result| Result | Proceed to |
| OK | A |
| NG (for LHD) | B |
| NG (for RHD) | C |
| | REPLACE MASTER CYLINDER SOLENOID ()
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| | REPLACE MASTER CYLINDER SOLENOID ()
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| A | |
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| REPLACE FRONT SPEED SENSOR ()
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