Test Mode Procedure

WARNING: This page is about a different car, the 2008 Toyota Tundra. 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 erased. 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 erased 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 parking or neutral 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.
9. Check that the ABS warning light and VSC OFF and SLIP indicator lights blink as shown below.
  
  Fig 1: Identifying ABS Warning Light - Blinking Pattern
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
10. Start the engine.
TEST MODE (SIGNAL CHECK) PROCEDURE (WHEN USING SST CHECK WIRE)
1. Place the vehicle on a level surface with an inclination of less than +/-10.
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 parking or neutral 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
  
  Fig 2: Identifying DLC3 Connector Terminal TS And CG
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. Turn the ignition switch to ON.
7. Check that the ABS warning light, VSC OFF indicator light and SLIP indicator light blink as shown below.
  
  Fig 3: Identifying ABS Warning Light - Blinking Pattern
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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 1 second.
  HINT:
  
  Ensure that the skid control buzzer beeps.
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 step 5 procedures). However, the yaw rate sensor check is only completed when the shift lever is moved to N or P.
  
  Fig 4: Identifying Start And End Position Of Parking Brake
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Stop the vehicle and move the shift lever to N or P.
3. Check that the skid control buzzer sounds for 3 seconds.
  HINT:
  - If the signal check has been completed normally, the skid control buzzer sounds and DTC C0371/71 will be deleted.
  - 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

VEHICLE SPEED REFERENCE TABLE

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 deleted.
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 below.
2. Check the reverse signal.
  1. Drive the vehicle in reverse for more than 1 second at 3 km/h (2 mph) or more.
    HINT:
    
    Drive the vehicle in reverse and check the speed sensor signal. Note that the signal check cannot be completed if the vehicle speed is 45 km/h (28 mph) or more.
    
    Fig 5: Identifying ABS Warning Light - Blinking Pattern
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check the forward signal.
  1. Drive the vehicle straight forward at a speed of 45 km/h (28 mph) or more for several seconds and check that the ABS warning light goes off.
    NOTE: The signal check may not be completed if the vehicle has its wheels spun or the steering wheel is turned during this check.
    
    Fig 6: Identifying Light Illumination Pattern - When Normal
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Stop the vehicle.
  NOTE:
  - The speed sensor signal check may not be completed if the speed sensor signal check is started while turning the steering wheel or spinning the wheels.
  - If the signal check has not been completed, the ABS warning light blinks while driving and the ABS system does not operate.
  HINT:
  
  When the signal check has been completed, the ABS warning light turns off while driving and blinks in the test mode pattern while stationary.
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
  
  Fig 7: Identifying DLC3 Connector Terminal TS And CG
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the ignition switch to ON.
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

ABS sensor:

DTC TABLE

DTC Code	Diagnosis	Trouble Areas
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:

DTC TABLE

DTC No.	Diagnosis	Trouble Areas
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 below.

Fig 9: Identifying Speed Sensor Frequency