Test Mode Procedure

WARNING: This page is about a different car, the 2009 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

By switching the skid control ECU from normal mode to test mode, abnormality detection sensitivity is enhanced and troubleshooting can be conducted efficiently.
Perform a sensor check in test mode after the speed sensor or sensor rotor has been repaired or replaced.
If the ignition switch is turned from ON to ACC or off during test mode, DTCs related to the signal check function will not be cleared. During test mode, do not change to normal mode.
During test mode, the skid control ECU stores all DTCs related to the signal check function, and the DTCs are cleared if normality is confirmed. Any remaining DTCs indicate abnormalities that were found.

TEST MODE (SIGNAL CHECK) PROCEDURE (WHEN USING TECHSTREAM)
1. Place the vehicle on a level surface with an inclination of less than +/-1°.
2. Turn the ignition switch off.
3. Check that the steering wheel is in the centered position.
4. Check that the shift lever is in P or N and apply the parking brake.
  CAUTION: Application of the parking brake is not necessary for entering test mode. However, apply the parking brake for safety.
5. Connect the Techstream to the DLC3.
6. Turn the ignition switch to ON.
7. Turn the Techstream ON.
8. Switch the skid control ECU to test mode using the Techstream.
  Enter the following menus: Chassis / ABS/VSC/ TRAC / Utility / Signal Check / All Signal Check or One Signal Check.
9. Check that the ABS warning light and VSC OFF indicator light blink as shown in the illustration.
10. Start the engine.
  
  Fig 1: Blinking Pattern In TEST MODE
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
TEST MODE (SIGNAL CHECK) PROCEDURE (WHEN USING SST CHECK WIRE)
1. Place the vehicle on a level surface with an inclination of less than +/-1°.
2. Turn the ignition switch off.
3. Check that the steering wheel is in the centered position.
4. Check that the shift lever is in P or N and apply the parking brake.
  CAUTION: Application of the parking brake is not necessary for entering test mode. However, apply the parking brake for safety.
5. Using SST, connect terminals 12 (TS) and 4 (CG) of the DLC3.
  SST 09843-18040
6. Turn the ignition switch to ON.
  
  Fig 2: Identifying Front View Of DLC3 Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
7. Check that the ABS warning light and VSC OFF indicator light blink as shown in the illustration.
8. Start the engine.
MASTER CYLINDER PRESSURE SENSOR CHECK
1. Leave the vehicle in a stationary condition and release the brake pedal for 1 second or more, and quickly depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more for 1 second.
2. Check that the skid control buzzer beeps for 3 seconds.
  HINT:
  
  Ensure that the skid control buzzer beeps.
  
  Fig 3: Blinking Pattern In TEST MODE
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
YAW RATE SENSOR CHECK
1. Release the parking brake and drive the vehicle at a speed of 3 km/h (2 mph) or more, and turn the steering wheel either to the left or right 90° or more to turn the vehicle 180°.
  HINT:
  
  The buzzer of the deceleration sensor check may sound while the vehicle is turning (refer to the 5 "Deceleration Sensor Check" procedures). However, the yaw rate sensor check is only completed when the shift lever is moved to N or P.
2. Stop the vehicle and move the shift lever to N or P.
3. Check that the skid control buzzer sounds for 3 seconds.
  
  Fig 4: Yaw Rate Sensor Start Position And End Position
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  - If the signal check has been completed normally, the skid control buzzer sounds and DTC C0371/ 71 will be cleared.
  - If the skid control buzzer does not sound, check the skid control buzzer circuit (See SKID CONTROL BUZZER CIRCUIT ). If the skid control buzzer still does not sound, there is a malfunction in the yaw rate sensor, so check for DTCs.
  - At the end of the 180° turn, the direction of the vehicle should be within 175 to 185° of its start position.
  - Do not spin the wheels.

DECELERATION SENSOR CHECK

Release the parking brake and drive the vehicle at a speed of 3 km/h (2 mph) or more, and turn the steering wheel either to the left or right 90° or more to turn the vehicle 180°.

Check that the skid control buzzer sounds for 3 seconds while the vehicle is turning.

HINT:

The skid control ECU checks whether the lateral acceleration reaches 0.1 G or more while the vehicle is turning. When the lateral acceleration reaches 0.1 G, the skid control buzzer sounds for 3 seconds.
The table shows the vehicle speeds and turning radius under which the lateral acceleration reaches 0.1 G or more.

Reference

REFERENCE CHART

Vehicle Speed km/h (mph)	Turning Radius m(ft.)
10(6)	7.87 (25.82)
15(9)	17.72 (58.13)
20 (12)	31.49 (103.31)
25 (16)	49.21 (161.45)

If the signal check has been completed normally, the skid control buzzer sounds and DTC C1279/ 79 will be cleared.
If the skid control buzzer does not sound, check the skid control buzzer circuit (See SKID CONTROL BUZZER CIRCUIT ). If the skid control buzzer still does not sound, there is a malfunction in the deceleration sensor, so check for DTCs.
Do not spin the wheels.

SPEED SENSOR CHECK
1. Check that the ABS warning light is blinking as shown in the illustration.
2. Check the speed sensor signal.
  1. Drive the vehicle straight forward at a speed of 45 km/h (28 mph) or more for several seconds.
  2. Check that the ABS warning light goes off.
    
    Fig 5: Blinking Pattern In TEST MODE
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    HINT:
    - The speed sensor check may not be completed if the sensor check is started with the steering wheel turned or one or more wheels spinning.
    - If the speed sensor check is commenced while the steering wheel is turned, the ABS warning light may come on after the low speed check is finished.
    - The ABS warning light comes on immediately when an abnormality is detected.
    - When the speed sensor signal is normal, the ABS warning light goes off while driving at 45 km/h (28 mph) or more and blinks in the test mode pattern while stationary.
    - After the ABS warning light goes off and if the vehicle speed exceeds 80 km/h (50 mph), a sensor check code will be stored again. Decelerate or stop the vehicle before the speed reaches 80 km/h (50 mph).
    - If the vehicle is driven on extremely rough or bumpy roads, sensor signal check may fail and middle speed check DTCs may not be cleared. In such cases, stop the vehicle and drive it again to resume the speed sensor check.
      
      Fig 6: Blinking Pattern Of Speed Sensor
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Stop the vehicle.
END OF SENSOR CHECK
1. When the sensor check is successfully completed, the ABS warning light blinks in the test mode pattern when the vehicle is stopped, and goes off when the vehicle is driven.
  NOTE: If the sensor check is not completed, the ABS warning light blinks even while the vehicle is driving and the ABS does not operate.
READ SIGNAL CHECK FUNCTION DTCs (WHEN USING TECHSTREAM)
1. Read the DTC(s) by following the instructions on the Techstream screen.
READ SENSOR SIGNAL CHECK FUNCTION DTCs (WHEN USING SST CHECK WIRE)
1. Using SST, connect terminals 4 (CG), 12 (TS) and 13 (TC) of the DLC3.
  SST 09843-18040
2. Turn the ignition switch to ON.
  
  Fig 7: Identifying Front View Of DLC3 Connector Terminal
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Read the number of blinks of the ABS warning light.
  HINT:
  
  If all sensors are normal, a normal system code is output (the light comes on at 0.25 second intervals).
4. After the check, disconnect SST from terminals 4 (CG), 12 (TS) and 13 (TC) of the DLC3.
5. Turn the ignition switch off.

SENSOR SIGNAL CHECK FUNCTION DTCs

Fig 8: Blinking Pattern Of Normal System Code

ABS Sensor

ABS SENSOR CHART

DTC No.	Diagnosis	Trouble Area
C1271/71	Low output signal of front speed sensor RH	Front speed sensor RH Speed sensor circuit Sensor installation
C1272/72	Low output signal of front speed sensor LH	Front speed sensor LH Speed sensor circuit Sensor installation
C1273/73	Low output signal of rear speed sensor RH	Rear speed sensor RH Speed sensor circuit Sensor installation
C1274/74	Low output signal of rear speed sensor LH	Rear speed sensor LH Speed sensor circuit Sensor installation
C1275/75	Abnormal change in output signal of front speed sensor RH	Sensor installation Speed sensor rotor Foreign matter on sensor tip or sensor rotor
C1276/76	Abnormal change in output signal of front speed sensor LH	Sensor installation Speed sensor rotor Foreign matter on sensor tip or sensor rotor
C1277/77	Abnormal change in output signal of rear speed sensor RH	Sensor installation Speed sensor rotor Foreign matter on sensor tip or sensor rotor
C1278/78	Abnormal change in output signal of rear speed sensor LH	Sensor installation Speed sensor rotor Foreign matter on sensor tip or sensor rotor
C1279/79	Deceleration sensor output voltage malfunction	Yaw rate sensor and deceleration sensor Sensor installation
C1281/81	Master cylinder pressure sensor output malfunction	Master cylinder pressure sensor

VSC Sensor

VSC SENSOR CHART

DTC No.	Diagnosis	Trouble Area
C0371/71	Yaw rate sensor	Yaw rate sensor

HINT:

The DTCs in this table are only output in test mode.
Detection of DTCs from C1271 /71 to C1274/74 is completed before the vehicle speed reaches 5 km/h (3 mph).
Detection of DTCs from C1275/75 to C1278/78 is completed before the vehicle speed reaches 45 km/h (28 mph).
C1271/71 to C1274/74: Speed sensor output from only one wheel is extremely low despite the other wheel speed outputs reaching 5 km/h (3 mph).
C1275/75 to C1278/78: Abnormal speed sensor output frequency is as shown in the illustration.

Fig 9: Blinking Pattern Of Speed Sensor Output
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002