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 in the ECU data monitor function of the hand-held tester.

1. Turn the power switch off and connect the hand-held tester to the DLC3.
2. Turn the ignition switch on. Follow the on-screen directions on the hand-held tester 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 ignition switch is turned on (initial check).

   Fig 1: Checking For Intermittent Problem Hand-held Tester

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   INTERMITTENT PROBLEMS
   
   

   Item	Measurement Item Range (Display)	Normal Condition
   SPDSEN FR	FR speed sensor open detection OPEN or NORMAL	NORMAL: Normal condition
   SPDSEN FL	FL speed sensor open detection OPEN or NORMAL	NORMAL: Normal condition
   SPD SEN RR	RR speed sensor open detection OPEN or NORMAL	NORMAL: Normal condition
   SPD SEN RL	RL speed sensor open detection OPEN or NORMAL	NORMAL: Normal condition
   TAWRATE SEN	Yaw rate sensor open detection	NORMAL: Normal condition
   DECELE SEN	G sensor open detection	NORMAL: Normal condition
   STEERING SEN	Steering sensor open detection	NORMAL: Normal condition
   M C SEN 1	Master Cylinder pressure sensor 1 open detection	NORMAL: Normal condition
   M C SEN 2	Master Cylinder pressure sensor 1 open detection	NORMAL: Normal condition
   STROKE SEN 1	Pedal stroke 1 open	NORMAL: Normal condition
   FR W C SEN	FR Wheel cylinder open	NORMAL: Normal condition
   FL W/C SEN	FR Wheel cylinder open	NORMAL: Normal condition
   RR W/C SEN	FR Wheel cylinder open	NORMAL: Normal condition
   RL W/C SEN	FR Wheel cylinder open	NORMAL: Normal condition
   Item	Measurement Item Range (Display)	Normal Condition
   HVCOM	HV communication open detection	NORMAL: Normal condition
   ACC SEN	Accumulator pressure sensor open detection	NORMAL: Normal condition

   HINT:

   • If the status remains on, check the continuity between the ECU and the sensors, or between ECUs.
   • The OPEN display on the hand-held tester remains on for 1 second after the harness signal changes from momentary interruption (open circuit) to normal condition.
     Fig 2: Harness Signals

     Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. While observing the screen, gently jiggle the connector or wire harness between the ECU and sensors, or between ECUs.

1. Result: Open-screen display does not change. 

HINT:

• The connector and or wire harness will be in momentary interruption (open circuit) if the chart fluctuates. Repair or replace connector and or wire harness as one of them is faulty.

Fig 3: Replacing Connector Or Wire Harness

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002