BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (w/o Vacuum Brake Booster): C1273,C1274,C1466,C1467; Low Output Signal of Rear Speed Sensor RH (Test Mode DTC); 2021 MY RAV4 RAV4 HV [08/2020

Last Modified: 01-30-2024	6.11:8.1.0	Doc ID: RM100000001QINT
Model Year Start: 2021	Model: RAV4	Prod Date Range: [08/2020 - 12/2021]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (w/o Vacuum Brake Booster): C1273,C1274,C1466,C1467; Low Output Signal of Rear Speed Sensor RH (Test Mode DTC); 2021 MY RAV4 RAV4 HV [08/2020 - 12/2021]

DTC

C1273

Low Output Signal of Rear Speed Sensor RH (Test Mode DTC)

DTC

C1274

Low Output Signal of Rear Speed Sensor LH (Test Mode DTC)

DTC

C1466

Rear Speed Sensor RH Circuit

DTC

C1467

Rear Speed Sensor LH Circuit

DESCRIPTION

Each speed sensor detects the wheel speed and sends the signals to the skid control ECU (brake booster with master cylinder assembly). These signals are used for ABS control.

DTCs C1273 and C1274 are cleared when the speed sensor sends a wheel speed signal or when Test Mode ends. DTCs C1273 and C1274 are output only in Test Mode.

DTC No.	Detection Item	INF Code	DTC Detection Condition	Trouble Area	Note
C1273	Low Output Signal of Rear Speed Sensor RH (Test Mode DTC)	-	Detected only during Test Mode.	Rear speed sensor RH Sensor installation Rear speed sensor rotor RH (Rear axle hub and bearing assembly RH) Skid control sensor wire RH (No. 1 parking brake wire assembly)	-
C1274	Low Output Signal of Rear Speed Sensor LH (Test Mode DTC)	-	Detected only during Test Mode.	Rear speed sensor LH Sensor installation Rear speed sensor rotor LH (Rear axle hub and bearing assembly LH) Skid control sensor wire LH (No. 2 parking brake wire assembly)	-
C1466	Rear Speed Sensor RH Circuit	521 522 523 524 526 527 528 529	INF Code: 521 At a vehicle speed of 10 km/h (6 mph) or more, speed sensor output from one or two wheels is lower than that from other wheels for 15 seconds or more. INF Code: 522 At a vehicle speed of 10 km/h (6 mph) or more, outputs from both front speed sensors are 0 km/h (0 mph) for 15 seconds or more. INF Code: 523 An open is detected in the speed sensor signal circuit for 0.5 seconds or more. INF Code: 524 Instantaneous interruption of sensor signal from the malfunctioning wheel occurs 255 times or more. INF Code: 526 When VM1 voltage is 8.6 V or more, sensor supply voltage drops for 0.5 seconds or more. INF Code: 527 At a vehicle speed of 10 km/h (6 mph) or more, speed sensor output from one wheel is 0 km/h (0 mph) for 1 second or more. INF Code: 528 When VM1 voltage is 8.6 V or more, sensor supply voltage drops for 60 seconds or more. INF Code: 529 Speed sensor output is 270 km/h (167 mph) or more continuously for 5 seconds or more.	INF Code: 521, 522, 524, 527 Open or short in speed sensor Improperly installed speed sensor, or abnormal clearance between sensor and rotor Open or short in wire harness Improperly connected connector, deformation or corrosion of terminals Rear speed sensor RH Skid control ECU (Brake booster with master cylinder assembly) INF Code: 523 Open or short in speed sensor Open or short in wire harness Improperly connected connector, deformation or corrosion of terminals Rear speed sensor RH Skid control ECU (Brake booster with master cylinder assembly) INF Code: 526, 528 Open or short in wire harness Skid control ECU (Brake booster with master cylinder assembly) INF Code: 529 Open or short in speed sensor Open or short in wire harness Rear speed sensor RH Skid control ECU (Brake booster with master cylinder assembly)	-
C1467	Rear Speed Sensor LH Circuit	531 532 533 534 536 537 538 539	INF Code: 531 At a vehicle speed of 10 km/h (6 mph) or more, speed sensor output from one or two wheels is lower than that from other wheels for 15 seconds or more. INF Code: 532 At a vehicle speed of 10 km/h (6 mph) or more, outputs from both front speed sensors are 0 km/h (0 mph) for 15 seconds or more. INF Code: 533 An open is detected in the speed sensor signal circuit for 0.5 seconds or more. INF Code: 534 Instantaneous interruption of sensor signal from the malfunctioning wheel occurs 255 times or more. INF Code: 536 When VM1 voltage is 8.6 V or more, sensor supply voltage drops for 0.5 seconds or more. INF Code: 537 At a vehicle speed of 10 km/h (6 mph) or more, speed sensor output from one wheel is 0 km/h (0 mph) for 1 second or more. INF Code: 538 When VM1 voltage is 8.6 V or more, sensor supply voltage drops for 60 seconds or more. INF Code: 539 Speed sensor output is 270 km/h (167 mph) or more continuously for 5 seconds or more.	INF Code: 531, 532, 534, 537 Open or short in speed sensor Improperly installed speed sensor, or abnormal clearance between sensor and rotor Open or short in wire harness Improperly connected connector, deformation or corrosion of terminals Rear speed sensor LH Skid control ECU (Brake booster with master cylinder assembly) INF Code: 533 Open or short in speed sensor Open or short in wire harness Improperly connected connector, deformation or corrosion of terminals Rear speed sensor LH Skid control ECU (Brake booster with master cylinder assembly) INF Code: 536, 538 Open or short in wire harness Skid control ECU (Brake booster with master cylinder assembly) INF Code: 539 Open or short in speed sensor Open or short in wire harness Rear speed sensor LH Skid control ECU (Brake booster with master cylinder assembly)	-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When replacing the skid control ECU (brake booster with master cylinder assembly), perform initialization and calibration of the linear solenoid valve.

Click here

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

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

Click here

Chassis > ABS/VSC/TRAC > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

RR Speed Open

Rear speed sensor RH open detection

Error or Normal

Normal: Momentary interruption not detected

After a momentary interruption occurs, if there is no momentary interruption for 1 second, it switches from "Error" to "Normal".

RL Speed Open

Rear speed sensor LH open detection

Error or Normal

Error: Momentary interruption detected

Normal: Momentary interruption not detected

After a momentary interruption occurs, if there is no momentary interruption for 1 second, it switches from "Error" to "Normal".

Chassis > ABS/VSC/TRAC > Data List

Tester Display
RR Speed Open
RL Speed Open

OK:

Normal (There are no momentary interruptions.)

HINT:

Perform the above inspection before removing the sensor and connector.

GO TO STEP 5

2.	READ VALUE USING TECHSTREAM (REAR SPEED SENSOR)

(a) Select the Data List on the Techstream.

Click here

Chassis > ABS/VSC/TRAC > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
RR Wheel Speed	Rear speed sensor RH	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 speed sensor LH	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

Chassis > ABS/VSC/TRAC > Data List

Tester Display
RR Wheel Speed
RL Wheel Speed

(b) Check 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.

Click here

OK:

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

GO TO STEP 5

3.	PERFORM TEST MODE INSPECTION (SIGNAL CHECK)

(a) Turn the ignition switch off.

(b) Perform the sensor check in Test Mode Procedure.

Click here

Chassis > ABS/VSC/TRAC > Utility

Tester Display
Signal Check

OK:

All Test Mode DTCs are cleared.

GO TO STEP 5

4.	RECONFIRM DTC

(a) Turn the ignition switch off.

(b) Clear the DTCs.

Click here

Chassis > ABS/VSC/TRAC > Clear DTCs

(d) Perform a road test.

(e) Check if the same DTC is output.

Click here

Chassis > ABS/VSC/TRAC > Trouble Codes

Result	Proceed to
DTCs C1466 and C1467 are not output.	A
DTCs C1466 and/or C1467 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.

Click here

USE SIMULATION METHOD TO CHECK

GO TO STEP 7

5.	CHECK REAR SPEED SENSOR INSTALLATION

(a) Turn the ignition switch off.

*a	No clearance
*b	OK
*c	NG

(b) Check the speed sensor installation.

Click here

OK:

There is no clearance between the sensor and the rear steering knuckle.

The installation bolt is tightened properly.

INSTALL REAR SPEED SENSOR CORRECTLY

6.	CHECK REAR SPEED SENSOR AND SENSOR ROTOR

(a) Remove the rear speed sensor and the component with the speed sensor rotor.

for Speed Sensor: Click here

for Speed Sensor Rotor: Click here

(b) Check the speed sensor tip and speed sensor rotor.

OK:

The sensor tip and rotor are free of scratches, oil, and foreign matter.

NOTICE:

If there are any ferrous metal filings stuck to the rotor, this will result in a malfunction, so confirm that the rotor is not contaminated with foreign matter before replacing the sensor.
If no damage to the speed sensor tip is found during this inspection, do not replace the speed sensor.
Check the speed sensor signal after cleaning or replacement.
Click here

CLEAN OR REPLACE REAR SPEED SENSOR OR COMPONENT WITH SENSOR ROTOR

7.	INSPECT PARKING BRAKE WIRE ASSEMBLY

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

*A	for RH
*B	for LH
*1	Skid Control Sensor Wire (Parking Brake Wire Assembly)
*a	Front view of wire harness connector (to Sensor Side Connector)
*b	Front view of wire harness connector (to Vehicle Side Connector)

(b) Disconnect the M50 or N58 skid control sensor wire (parking brake wire assembly) connector.

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

Standard Resistance:

for RH

Tester Connection	Condition	Specified Condition
M50-2 (RA+) - MM3-3	Always	Below 1 Ω
M50-2 (RA+) or MM3-3 - Body ground and other terminals	Always	10 kΩ or higher
M50-1 (RA-) - MM3-4	Always	Below 1 Ω
M50-1 (RA-) or MM3-4 - Body ground and other terminals	Always	10 kΩ or higher

for LH

Tester Connection	Condition	Specified Condition
N58-2 (LA+) - NN6-3	Always	Below 1 Ω
N58-2 (LA+) or NN6-3 - Body ground and other terminals	Always	10 kΩ or higher
N58-1 (LA-) - NN6-4	Always	Below 1 Ω
N58-1 (LA-) or NN6-4 - Body ground and other terminals	Always	10 kΩ or higher

NOTICE:

Check the speed sensor signal after replacement.

Click here

REPLACE PARKING BRAKE WIRE ASSEMBLY

8.	CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - REAR SPEED SENSOR)

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

(b) Reconnect the MM3 or NN6 skid control sensor wire (parking brake wire assembly) connector.

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

Standard Resistance:

for RH

Tester Connection	Condition	Specified Condition
A42-22 (RR+) - M50-2 (RA+)	Always	Below 1 Ω
A42-22 (RR+) or M50-2 (RA+) - Body ground	Always	10 kΩ or higher
A42-9 (RR-) - M50-1 (RA-)	Always	Below 1 Ω
A42-9 (RR-) or M50-1 (RA-) - Body ground	Always	10 kΩ or higher

for LH

Tester Connection	Condition	Specified Condition
A42-20 (RL+) - N58-2 (LA+)	Always	Below 1 Ω
A42-20 (RL+) or N58-2 (LA+) - Body ground	Always	10 kΩ or higher
A42-7 (RL-) - N58-1 (LA-)	Always	Below 1 Ω
A42-7 (RL-) or N58-1 (LA-) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

9.	INSPECT BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SENSOR OUTPUT)

(a) Reconnect the A42 skid control ECU (brake booster with master cylinder assembly) connector.

for RH

for LH

Front view of wire harness connector

(to Rear Speed Sensor)

(b) Turn the ignition switch to ON.

Standard Voltage:

for RH

Tester Connection	Condition	Specified Condition
M50-2 (RA+) - Body ground	Ignition switch ON	5.7 to 14 V

for LH

Tester Connection	Condition	Specified Condition
N58-2 (LA+) - Body ground	Ignition switch ON	5.7 to 14 V

REPLACE REAR SPEED SENSOR

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY