Anti-Lock Brake System Check For Intermittent Problems

Brake. Corolla. Zre142 Aze141
Brake Control Dynamic Control Systems. Corolla. Zre142 Aze141

  1. CHECK FOR INTERMITTENT PROBLEMS

Anti-Lock Brake System -- Check For Intermittent Problems



CHECK FOR INTERMITTENT PROBLEMS
HINT:
A momentary interruption (open circuit) in the connectors and/or wire harness between the sensors and ECUs can be detected using the ECU Data List function of the Techstream.

  1. Turn the ignition switch off.

  2. Connect the Techstream to the DLC3.

  3. Turn the ignition switch to ON.

  4. Turn the Techstream on.



    5. Corolla. Zre142 Aze141.Brake Control Dynamic Control Systems.Anti-Lock Brake System.Anti-Lock Brake System Check For Intermittent Problems

  5. Follow the directions on the Techstream to display the Data List and select areas where momentary interruption should be monitored.

    HINT:
    1. A momentary interruption (open circuit) cannot be detected for 3 seconds after the ignition switch is turned to ON (initial check).
    2. If the status remains on (ERROR displayed), check for continuity between the ECU and the sensors, or between ECUs.
    3. The ERROR display on the Techstream remains on for 1 second after the harness signal changed from momentary interruption (open circuit) to normal condition.

    ABS/VSC/TRAC
    Tester Display
    		Measurement Item / Range
    		Normal Condition
    		Diagnostic Note
    FR Speed Open
    		FR speed sensor open detection / ERROR or NORMAL
    		ERROR: Momentary interruption
    NORMAL: Normal
    		-
    FL Speed Open
    		FL speed sensor open detection / ERROR or NORMAL
    		ERROR: Momentary interruption
    NORMAL: Normal
    		-
    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
    		-


    6. Corolla. Zre142 Aze141

  6. While observing the screen, gently jiggle the connector or wire harness between the ECU and sensors, or between ECUs.

    OK:
    NORMAL display appears.
    HINT:
    The connector and/or wire harness has a momentary interruption (open circuit) if the display changes. Repair or replace the connector and/or wire harness as one of them is faulty.