BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1407,C1408; Open or Short in Rear Speed Sensor RH Circuit; 2016 - 2017 MY Sienna [12/2015

Last Modified: 04-05-2023	6.11:8.1.0	Doc ID: RM100000000VIVS
Model Year Start: 2016	Model: Sienna	Prod Date Range: [12/2015 - 11/2017]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1407,C1408; Open or Short in Rear Speed Sensor RH Circuit; 2016 - 2017 MY Sienna [12/2015 - 11/2017]

DTC

C1407

Open or Short in Rear Speed Sensor RH Circuit

DTC

C1408

Open or Short in Rear Speed Sensor LH Circuit

DESCRIPTION

The speed sensor detects wheel speed and sends the appropriate signals to the skid control ECU. These signals are used for ABS control.

Speed sensor rotors have rows of alternating N and S magnetic poles and their magnetic fields change when the rotors turn. Each speed sensor detects that magnetic change and sends a pulse signal to the skid control ECU (for 2WD).
Speed sensor rotors have 48 serrations and their magnetic fields change when the rotors turn. Each speed sensor detects that magnetic change and sends a pulse signal to the skid control ECU (for AWD).

The hall IC type speed sensor uses the frequency of output pulses to detect the vehicle speed. Because the sensor outputs digital pulses, it can detect vehicle speeds even when the vehicle is nearly stationary.

HINT:

Measure the connection status between the sensor connector and the vehicle wire harness.

DTC Code

DTC Detection Condition

Trouble Area

C1407

C1408

Either of the following is detected:

An open in the speed sensor signal circuit continues for 0.5 seconds or more.
With the IG1 terminal voltage 9.5 V or more, the sensor power supply voltage decreases for 0.5 seconds or more.

Rear speed sensor RH/LH
Speed sensor circuit
Brake actuator assembly (Skid control ECU)

HINT:

DTC C1407 is for the rear speed sensor RH.
DTC C1408 is for the rear speed sensor LH.

WIRING DIAGRAM

Refer to DTCs C1403 and C1404 (See page ).

CAUTION / NOTICE / HINT

NOTICE:

When replacing the brake actuator assembly, perform zero point calibration and store system information (See page ).

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

(a) Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC (See page ).

ABS/VSC/TRAC

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

RR Speed Open

RR speed sensor open detection / Error or Normal

Error: Momentary interruption

Normal: Normal

RL Speed Open

RL speed sensor open detection / Error or Normal

Error: Momentary interruption

Normal: Normal

Result

Result	Proceed to
There are no momentary interruptions	A
There are momentary interruptions	B

HINT:

Perform the above inspection before removing the sensor and connector.

GO TO STEP 4

2.	READ VALUE USING TECHSTREAM (REAR SPEED SENSOR)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / ABS/VSC/ TRAC / Data List.

(f) Select the Data List on the Techstream (See page ).

ABS/VSC/TRAC

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
RR Wheel Speed	Rear wheel speed sensor RH reading / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)	Vehicle stopped: 0 km/h (0 mph)	When driving at constant speed: No large fluctuations
RL Wheel Speed	Rear wheel speed sensor LH reading / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)	Vehicle stopped: 0 km/h (0 mph)	When driving at constant speed: No large fluctuations

(g) Check that the speed value output from the speed sensor displayed on the Techstream.

HINT:

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, see the reference chart (See page ).

OK:

The speed value output from the speed sensor displayed on the Techstream is the similar speed as indicated on the speedometer.

GO TO STEP 4

3.	RECONFIRM DTC

(a) Turn the ignition switch off.

(b) Clear the DTCs (See page ).

(d) Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

(e) Check if the same DTC is recorded (See page ).

Result

Result	Proceed to
DTCs (C1407 and C1408) are not output	A
DTCs (C1407 and/or C1408) are output	B

HINT:

If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step (See page ).

CHECK FOR INTERMITTENT PROBLEMS

(See page )

REPLACE BRAKE ACTUATOR ASSEMBLY

4.	CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR SPEED SENSOR)

(a) for 2WD

(1) Make sure that there is no looseness at the locking part and the connecting part of the connector.

(2) Disconnect the skid control ECU connector.

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

Standard Resistance:

for RH

Tester Connection	Condition	Specified Condition
A4-17 (RR+) - k1-2 (RR+)	Always	Below 1 Ω
A4-17 (RR+) - Body ground	Always	10 kΩ or higher
A4-16 (RR-) - k1-1 (RR-)	Always	Below 1 Ω
A4-16 (RR-) - Body ground	Always	10 kΩ or higher

for LH

Tester Connection	Condition	Specified Condition
A4-5 (RL+) - n1-2 (RL+)	Always	Below 1 Ω
A4-5 (RL+) - Body ground	Always	10 kΩ or higher
A4-4 (RL-) - n1-1 (RL-)	Always	Below 1 Ω
A4-4 (RL-) - Body ground	Always	10 kΩ or higher

(b) for AWD

(1) Make sure that there is no looseness at the locking part and the connecting part of the connector.

(2) Disconnect the skid control ECU connector.

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

Standard Resistance:

for RH

Tester Connection	Condition	Specified Condition
A4-17 (RR+) - L41-1 (RR+)	Always	Below 1 Ω
A4-17 (RR+) - Body ground	Always	10 kΩ or higher
A4-16 (RR-) - L41-2 (RR-)	Always	Below 1 Ω
A4-16 (RR-) - Body ground	Always	10 kΩ or higher

for LH

Tester Connection	Condition	Specified Condition
A4-5 (RL+) - K30-1 (RL+)	Always	Below 1 Ω
A4-5 (RL+) - Body ground	Always	10 kΩ or higher
A4-4 (RL-) - K30-2 (RL-)	Always	Below 1 Ω
A4-4 (RL-) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	INSPECT SKID CONTROL ECU (SENSOR INPUT)

(a) for 2WD

(1) Reconnect the skid control ECU connector.

(2) Turn the ignition switch to ON.

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

Standard Voltage:

for RH

Tester Connection	Switch Condition	Specified Condition
k1-2 (RR+) - Body ground	Ignition switch ON	8 to 14 V

for LH

Tester Connection	Switch Condition	Specified Condition
n1-2 (RL+) - Body ground	Ignition switch ON	8 to 14 V

Text in Illustration

*a	Front view of wire harness connector (to Rear Speed Sensor)

(b) for AWD

(1) Reconnect the skid control ECU connector.

(2) Turn the ignition switch to ON.

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

Standard Voltage:

for RH

Tester Connection	Switch Condition	Specified Condition
L41-1 (RR+) - Body ground	Ignition switch ON	8 to 14 V

for LH

Tester Connection	Switch Condition	Specified Condition
K30-1 (RL+) - Body ground	Ignition switch ON	8 to 14 V

Text in Illustration

*a	Front view of wire harness connector (to Rear Speed Sensor)

Result

Result	Proceed to
OK (for 2WD)	A
OK (for AWD)	B
NG	C

NOTICE:

Check the speed sensor signal after replacement (See page ).

HINT:

If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step (See page ).

REPLACE REAR AXLE HUB AND BEARING ASSEMBLY

REPLACE REAR SPEED SENSOR

REPLACE BRAKE ACTUATOR ASSEMBLY