Test Mode Procedure

HINT:

• By switching the skid control ECU from normal mode to test mode, abnormality detection sensitivity is enhanced and troubleshooting can be conducted efficiently.
  Fig 1: Inspecting Connector And Wire Harness Between ECU Or Sensors

  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
• 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 be erased.
• 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 are those indicating abnormalities that were found.

1. TEST MODE (SIGNAL CHECK) PROCEDURE (USING TECHSTREAM) 
   1. Turn the ignition switch off.
   2. Check that the steering wheel is in the straight-ahead position.
   3. A/T: Check that the shift lever is in the P position and apply the parking brake.
   4. M/T: Check that the shift lever is in neutral and apply the parking brake.
   5. Connect the Techstream to the DLC3.
   6. Turn the ignition switch to ON.
   7. Turn the tester on.
   8. Switch the skid control ECU to test mode using the Techstream.

      Select the following menu items: Chassis/ABS/ VSC/TRAC/Utility/Signal Check.

   9. Check that the ABS warning light blinks as shown in the illustration.

      HINT:

      If the ABS warning light does not blink, perform relevant troubleshooting procedures. The relevant troubleshooting procedures are described in the sections listed in the table below.

      ABS WARNING LIGHT REFERENCE CHART
      
      

      Section Title	Reference
      ABS Warning Light does not Come ON	ABS WARNING LIGHT DOES NOT COME ON
      TS and CG Terminal Circuit	TS AND CG TERMINAL CIRCUIT

      Fig 2: Identifying ABS Warning Light Blinking Pattern

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   10. Start the engine.
2. SPEED SENSOR CHECK (USING TECHSTREAM) 
   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 28 mph (45 km/h) or more for several seconds.
      2. Check that the ABS warning light goes off.
         Fig 3: Identifying ABS Warning Light Blinking Pattern

         Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

         HINT:

         • The sensor check may not be completed if one or more wheels spin or the steering wheel is turned.
         • 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 the vehicle is driven at 28 mph (45 km/h) or more and blinks in the test mode pattern while stationary.
         • Do not drive the vehicle at a speed of 50 mph (80 km/h) or more after the ABS warning light turns off, because test mode DTCs are set again when the vehicle speed exceeds 50 mph (80km/h).
           Fig 4: Identifying Blinking Pattern (Speed Sensor Check)

           Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Stop the vehicle.
3. END SENSOR CHECK (USING TECHSTREAM) 
   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 driven and the ABS does not operate.
4. READ SIGNAL CHECK FUNCTION DTCS (USING TECHSTREAM) 
   1. Read the DTC(s) by following the instructions on the tester screen.

      HINT:

      See the list of DTCs (refer to step  9).

5. TEST MODE (SIGNAL CHECK) PROCEDURE (USING SST CHECK WIRE) 
   1. Turn the ignition switch off.
   2. Check that the steering wheel is in the straight-ahead position.
   3. A/T: Check that the shift lever is in the P position and apply the parking brake.
   4. M/T: Check that the shift lever is in neutral and apply the parking brake.
   5. Using SST, connect terminals TS and CG of the DLC3.

      SST 09843-18040 

   6. Turn the ignition switch to ON.
      Fig 5: Identifying TS And CG Of DLC3 Connector Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   7. Check that the ABS warning light blinks as shown in the illustration.

      HINT:

      If the ABS warning light does not blink, perform relevant troubleshooting procedures. The relevant troubleshooting procedures are described in the sections listed in the table below.

      ABS WARNING LIGHT REFERENCE CHART
      
      

      Section Title	Reference
      ABS Warning Light does not Come ON	ABS WARNING LIGHT DOES NOT COME ON
      TS and CG Terminal Circuit	TS AND CG TERMINAL CIRCUIT

      Fig 6: Identifying ABS Warning Light Blinking Pattern

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   8. Start the engine.
6. SPEED SENSOR CHECK (USING SST CHECK WIRE) 
   1. Check that the ABS warning light blinks as shown in the illustration.
   2. Check the speed sensor signal.
      1. Drive the vehicle straight forward at a speed of 28 mph (45km/h) or more for several seconds, and then step on the brake pedal.
      2. Check that the ABS warning light goes off.
         Fig 7: Identifying ABS Warning Light Blinking Pattern

         Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

         HINT:

         • The sensor check may not be completed if one or more wheels spin or the steering wheel is turned.
         • 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 the vehicle is driven at 28 mph (45 km/h) or more and blinks in the test mode pattern while stationary.
         • Do not drive the vehicle at a speed of 50 mph (80 km/h) or more after the ABS warning light turns off, because test mode DTCs are set again when the vehicle speed exceeds 50 mph (80km/h).
           Fig 8: Identifying Blinking Pattern (Speed Sensor Check)

           Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Stop the vehicle.
7. END SENSOR CHECK (USING SST CHECK WIRE) 
   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 driven and the ABS does not operate.
8. READ SIGNAL CHECK FUNCTION DTCS (USING SST CHECK WIRE) 
   1. Using SST, connect terminals TC and CG of the DLC3.

      SST 09843-18040 

   2. Turn the ignition switch to ON.
   3. Read the number of blinks of the ABS warning light.

      HINT:

      • See the list of DTCs (refer to step 9).
        Fig 9: Identifying TC And CG Of DLC3 Connector Terminals

        Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • If all the sensors are normal, a normal system code is output (the light comes on for 0.25 seconds at intervals of 0.25 seconds).
   4. After the check, disconnect the SST from terminals TC and CG of the DLC3.
   5. Turn the ignition switch off.
9. SPEED SENSOR CHECK FUNCTION DTCs 
   Fig 10: Identifying ABS Warning Light Blinking Pattern

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TROUBLE AREAS DIAGNOSIS CHART
   
   

   Code No.	Diagnosis	Trouble Areas
   C1271/71	Low output signal of front speed sensor RH	Front speed sensor RH Front speed sensor RH circuit Sensor installation Foreign matter on sensor tip or sensor rotor
   C1272/72	Low output signal of front speed sensor LH	Front speed sensor LH Front speed sensor LH circuit Sensor installation Foreign matter on sensor tip or sensor rotor
   C1273/73	Low output signal of rear speed sensor RH	Skid control sensor RH Skid control sensor RH circuit Sensor installation
   C1274/74	Low output signal of rear speed sensor LH	Skid control sensor LH Skid control sensor LH circuit Sensor installation
   C1275/75	Abnormal change in output signal of front speed sensor RH	Front speed sensor RH Front speed sensor RH circuit Foreign matter on sensor tip or sensor rotor
   C1276/76	Abnormal change in output signal of front speed sensor LH	Front speed sensor LH Front speed sensor LH circuit Foreign matter on sensor tip or sensor rotor
   C1277/77	Abnormal change in output signal of rear speed sensor RH	Skid control sensor RH Skid control sensor RH circuit
   C1278/78	Abnormal change in output signal of rear speed sensor LH	Skid control sensor LH Skid control sensor LH circuit

   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 3 mph (5 km/h).
   • Detection of DTCs from C1275/75 to C1278/78 is completed several seconds after the vehicle speed exceeds 28 mph (45 km/h).
   • C1271/71 - C1274/74: Speed output from only one wheel is extremely low despite other wheel speed outputs reaching 3 mph (5 km/h).
   • C1275/75 - C1278/78: Abnormal speed sensor output frequency is as shown in the illustration.