Check For Intermittent Problems [10/2015 - ]

HINT: 

A momentary interruption (open circuit) in the connectors and/or wire harnesses between the sensors and ECUs can be detected using the ECU 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 interruptions 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 Error is displayed, measure the resistance between the ECUs and sensors or between ECUs.
   • Error remains displayed on the Techstream for 1 second after the harness signal changes from a momentary interruption (open circuit) to normal.
   ABS/VSC/TRAC
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   FR Speed Open	Front speed sensor RH open detection/ Error or Normal	Normal	-
   FL Speed Open	Front speed sensor LH open detection/ Error or Normal	Normal	-
   RR Speed Open	Rear speed sensor RH open detection/ Error or Normal	Normal	-
   RL Speed Open	Rear speed sensor LH open detection/ Error or Normal	Normal	-
   EFI Communication Open	EFI communication open detection/ Error or Normal	Normal	-
   Yaw Rate Open	Yaw rate sensor open detection/ Error or Normal	Normal	-
   Deceleration Open	Acceleration sensor open detection/ Error or Normal	Normal	-
   Steering Open	Steering sensor open detection/ Error or Normal	Normal	-
   Master Cylinder Open	Master cylinder pressure sensor open detection/ Error or Normal	Normal	-
   FR Speed Sensor Voltage Open	Front speed sensor RH voltage open detection/ Error or Normal	Normal	-
   FL Speed Sensor Voltage Open	Front speed sensor LH voltage open detection/ Error or Normal	Normal	-
   RR Speed Sensor Voltage Open	Rear speed sensor RH voltage open detection/ Error or Normal	Normal	-
   RL Speed Sensor Voltage Open	Rear speed sensor LH voltage open detection/ Error or Normal	Normal	-
   M/C Pressure Sensor Noise	Master cylinder pressure sensor noise detection/ Error or Normal	Normal	-
   Brake Pedal Switch Open	Brake pedal load sensing switch open detection/ Error or Normal	Normal	-
   Yaw Rate Sensor Voltage Open	Yaw rate sensor voltage open detection/ Error or Normal	Normal	-
   EFI Communication Invalid	EFI communication invalid detection/ Error or Normal	Normal	-
   Master Cylinder Pressure Sensor Power Supply Open	Master cylinder pressure sensor power supply voltage status	Normal	-
   Solenoid Power Supply Open	Solenoid Power Supply Open	Normal	-
   Motor Power Supply Open	Motor power supply voltage status	Normal	-
   Stop Switch Open	Momentary interruption (open circuit) status in the wire harness between the skid control ECU (brake actuator assembly) and the stop light switch assembly	Normal	-

6. While observing the screen, gently jiggle the connectors or wire harnesses between the ECUs and sensors or between ECUs.

   OK

   Normal display does not change.

   HINT: 

   If the display changes, the connector and/or the wire harness has caused a momentary interruption of the circuit. Repair or replace the connector and/or wire harness as one of them is faulty.