Check For Intermittent Problems [10/2023 - ]

HINT: 

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

1. Turn the engine switch off.
2. Connect the Techstream to the DLC3.
3. Turn the engine switch on (IG).
4. Turn the Techstream on.
5. Follow the directions on the Techstream to display the Data List and select areas where momentary interruption should be monitored.

   HINT: 

   • A momentary interruption (open circuit) cannot be detected for 3 seconds after the engine switch is turned on (IG) (initial check).
   • If Under intermittent remains displayed for one of the items on the Techstream, check for continuity between the ECU and the item for which Under intermittent is displayed.
   • If a momentary interruption occurs and Under intermittent is displayed on the Techstream, Under intermittent will remain displayed on the Techstream for 1 second after the circuit returns to normal.

   Chassis > Brake > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   FR Speed Open	Front speed sensor RH open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0506-14, C14E3-14
   FL Speed Open	Front speed sensor LH open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0500-14, C14E0-14
   RR Speed Open	Rear speed sensor RH open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0512-14, C14E9-14
   RL Speed Open	Rear speed sensor LH open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C050C-14, C14E6-14
   EFI Communication Open	ECM communication open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related Vehicle Control History (RoB): X2079 Related DTC: U0100-87
   Yaw Rate Open	Yaw rate sensor open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: U0125-87
   Deceleration Open	Acceleration sensor open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: U0125-87
   Steering Open	Steering angle sensor open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: U0126-87
   Master Cylinder Open	Master cylinder pressure sensor open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0540-31
   FR Speed Sensor Voltage Open	Front speed sensor RH voltage open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0506-1F
   FL Speed Sensor Voltage Open	Front speed sensor LH voltage open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0500-1F
   RR Speed Sensor Voltage Open	Rear speed sensor RH voltage open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0512-1F
   RL Speed Sensor Voltage Open	Rear speed sensor LH voltage open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C050C-1F
   M/C Pressure Sensor Noise	Master cylinder pressure sensor noise detection	Under intermittent or Normal	Under intermittent: Noise detected Normal: Noise not detected	After noise occurs, if there is no noise for 5 seconds, it switches from "Under intermittent" to "Normal". Related DTC: C0540-49
   Brake Pedal Switch Open	Brake pedal load sensing switch open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0040-13
   Yaw Rate Sensor Voltage Open	Yaw rate sensor voltage open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C14D7-1C
   EFI Communication Invalid	ECM communication invalid detection	Under intermittent or Normal	Under intermittent: ECM communication invalid state detected Normal: ECM communication invalid state not detected	After ECM communication invalid state occurs, if there no further invalid state occurs, it switches from "Under intermittent" to "Normal". Related Vehicle Control History (RoB): X2079 Related DTC: U0100-87
   Master Cylinder Pressure Sensor Power Supply Open	Master cylinder pressure sensor power supply voltage status	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0540-49
   Solenoid Power Supply Open	Solenoid power supply voltage status	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C143A-7F
   Motor Power Supply Open	Motor power supply voltage status	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C052F-14
   Stop Switch Open	Momentary interruption (open circuit) status in wire harness between skid control ECU (brake actuator assembly) and stop light switch assembly status	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related DTC: C0540-17, C1380-7E, C1380-7F, P0571-13
   Air Bag ECU Communication Open	Air bag ECU communication open detection	Under intermittent or Normal	Under intermittent: 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 "Under intermittent" to "Normal". Related Vehicle Control History (RoB): X2086 Related DTC: U0151-87

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

   OK

   Normal is displayed.

   HINT: 

   If the display changes, this indicates that there has been a momentary interruption (open circuit) in the connector and/or wire harness. In this case, repair or replace the connectors and/or wire harnesses as one of them is faulty.

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

   OK

   Normal is displayed.

   HINT: 

   • If a momentary interruption occurs and Under intermittent is displayed on the Techstream, Under intermittent will remain displayed on the Techstream for 1 second after the circuit returns to normal.

     Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   • If the display changes, this indicates that there has been a momentary interruption (open circuit) in the connector and/or wire harness. In this case, repair or replace the connectors and/or wire harnesses as one of them is faulty.